KDP Rejected Your ISBN: Fixing “Please fix the highlighted issue” and Imprint Mismatch Errors

Your book is finished, you paid for your own ISBN, and now the Publish button won't cooperate. In most cases KDP is comparing one string of text against another — and losing over a capital letter or a trailing space.

You chose “Use my own ISBN” on the paperback or hardcover setup page, entered the number and your imprint, and KDP answered with “Please fix the highlighted issue” — sometimes with nothing visibly highlighted at all. Or you got a more specific complaint publishers often report: “The imprint registered to this ISBN does not match this imprint,” an invalid ISBN, or an ISBN already in use. Here is what KDP actually checks and the order to fix it in.

What this error actually means

When you bring your own ISBN, Amazon does not take your word for it: KDP validates the number and its metadata against the record held by the agency that issued it — for US publishers, Bowker (myidentifiers.com). Amazon's help pages are explicit on two points: the ISBN and imprint fields are case-sensitive, and every detail has to line up exactly with what the agency has on file. Any mismatch in the ISBN, imprint (publisher name), title, or author blocks publication.

“Exactly” is the operative word. Maple Street Press and Maple Street Press LLC are different imprints to this check; so is the same name with an invisible trailing space, which KDP specifically warns about. And per Amazon's troubleshooting page, the vague “highlighted issue” message with nothing actually highlighted is most often exactly this: an ISBN/imprint pairing the system could not reconcile.

This validation is a registry comparison, not just a math check: an ISBN with a perfectly fine checksum can still be rejected over metadata, and a number no agency ever issued can still have a valid check digit (see how check digits work for that distinction).

The fix path, in order

Work through these checks in order; each one you pass narrows where the problem lives.

1. First, confirm the number itself is a valid ISBN-13. KDP describes an ISBN as a 13-digit identifier, so count the digits. If your certificate shows a 10-digit ISBN, do not just type 978 in front of it — conversion changes the final check digit, so the naive version fails validation. Run it through the ISBN-10 to ISBN-13 converter, which recomputes the checksum in both directions. Also watch for spreadsheet damage: an ISBN-10 starting with 0 may have silently lost its leading zero in Excel (here's why, and how to prevent it). If the checksum fails, one digit is mistyped — compare against your purchase confirmation character by character.

2. If the number is valid, check which ISBN option you selected. A free KDP ISBN is available for paperbacks and hardcovers only, is registered under the imprint “Independently published,” and can only be used on KDP — it cannot carry the book to other platforms. Your own ISBN can travel anywhere, but it drags the exact-match requirement with it. If you meant to use your own number, make sure the form is actually in “Use my own ISBN” mode.

3. If the option is right, make the imprint match the agency record exactly. Log in to your Bowker (or national agency) account, open the record for this specific ISBN, copy the publisher/imprint name on file, and paste it into KDP's imprint field. Do the same for the title and author name, which are checked too. Don't trust memory: most “imprint does not match” cases are one comma, one “LLC,” or one capital letter away from the publisher's own registration.

4. If you just edited the Bowker record, wait. Amazon's help pages allow up to 5 business days before edits made on the Bowker side are reflected in KDP. Resubmitting immediately after an agency-side fix usually reproduces the same error — not because the fix was wrong, but because KDP hasn't seen it yet. Correct once, note the date, and resubmit after the window.

5. If KDP says the ISBN is already in use, check your own Bookshelf first. Per KDP's guidelines, the same ISBN cannot be reused across book formats or for a new edition with significant changes: the eBook (where an ISBN is optional anyway), paperback, and hardcover each need their own number. A common trap is an ISBN attached to an earlier draft or the wrong format in your own account. An unpublished draft's ISBN can be edited or removed; a published book's cannot be changed, so a number locked to a live title cannot be moved.

What won't work

• Resubmitting the same data repeatedly. The comparison is deterministic; identical fields get the identical answer.
• Prepending 978 to an ISBN-10 by hand. The check digit changes in conversion; use a converter that recomputes it.
• Swapping the ISBN on a published book. Amazon's help is unambiguous: ISBNs cannot be changed once published. The realistic route is a new edition under the new ISBN.
• Using a free KDP ISBN outside Amazon. It is restricted to KDP; wide distribution needs your own number.
• Passing a checksum test and calling it done. A valid check digit proves internal consistency, not that the number is registered to you or that the agency record matches your fields.

IngramSpark users report the same family of imprint- and title-mismatch rejections, with the same remedy: make what you type match the Bowker record character for character, and allow time for recent edits to propagate.

What to send support if nothing works

If every check passes and the error persists past the 5-business-day window, contact KDP support through your account and include everything in the first message:

• The full ISBN-13, exactly as entered;
• A screenshot of the agency record (Bowker/myidentifiers) showing the imprint, title, and author on file;
• The exact strings you entered in KDP's imprint, title, and author fields — pasted as text, not described;
• The date of any recent changes you made to the agency record;
• The book format (paperback/hardcover) and a screenshot of the error message itself.

That package lets an agent compare both sides immediately. If the mismatch turns out to be on the agency side, the correction happens at Bowker or your national agency — Amazon can't edit their records.

Related errors on other platforms

Your ISBN doubles as the book's EAN-13 barcode everywhere else, so the same number can hit different walls. If Amazon Seller Central (not KDP) rejects it on a product listing, that is a marketplace GTIN check — see fixing invalid GTIN errors on Amazon. Selling the book directly, you may meet the equivalents on Shopify, eBay, or Google Merchant Center. Preparing a cover outside KDP? The barcode generator renders an EAN-13 from your ISBN-13.

FAQ

Why does KDP say the imprint registered to this ISBN does not match?

KDP compares the imprint you typed against the publisher name recorded with your ISBN agency (Bowker in the US), and the comparison is exact and case-sensitive: different capitalization, a missing "LLC," extra punctuation, or a trailing space all count as mismatches. Copy the imprint from the agency's ISBN record and paste it into KDP rather than retyping it.

Can I enter an ISBN-10 on KDP?

KDP describes an ISBN as a 13-digit identifier, so enter the 13-digit form. If your paperwork shows a 10-digit ISBN, convert it properly: the 978 prefix plus the first nine digits plus a freshly computed check digit. Just typing 978 in front produces an invalid code, because the final digit changes under the new checksum.

How long do Bowker changes take to show up on KDP?

Amazon's KDP help pages allow up to five business days for edits you make to an ISBN record on Bowker to reach KDP's systems. If you just corrected the imprint, title, or author on the agency side, wait out that window before resubmitting.

Can I use the same ISBN for my paperback and hardcover on KDP?

No. KDP's guidelines state the same ISBN cannot be reused across book formats or for a new edition with significant changes: paperback, hardcover, and any revised edition each need their own ISBN. If KDP reports an ISBN as already in use, check whether it is attached to another format or title in your Bookshelf.

This guide is for general information only; CodeClassify is not affiliated with or endorsed by Amazon, KDP, IngramSpark, or Bowker. Checksum validation confirms internal consistency, not registration. Platform behavior and time frames change; confirm current requirements on the official KDP help pages and with your national ISBN agency.