1. Go to folio.frontside.io
2. Search for title [before title test] or use URL https://folio.frontside.io/eholdings/titles/17290132
3. Edit record
4. Add an author Dennis, Miller and an editor Brady, Wayne
5. Save successfully
6. Edit same record and add another author Allen, Ed
7. Hit save and the following error message displays: An unknown error occurred

Same issue can be reproduced when adding identifiers

1. Go to folio.frontside.io

2. Search for title [Mary] or use URL https://folio.frontside.io/eholdings/titles/172364263
3. Edit record
4. Add multiple identifiers
5. Save successfully
6. Edit same record and add another identifier
7. Hit save and the following error message displays: An unknown error occurred

Additional details

https://okapi.frontside.io/eholdings/resources/123355-2867674-17290132

request body
{"data":{"id":"123355-2867674-17290132","type":"resources","attributes":{"description":"","edition":"2nd","isPeerReviewed":true,"isTitleCustom":true,"publisherName":"Wales","titleId":17290132,"contributors":[{"type":"editor","contributor":"Brady, Wayne"},{"type":"author","contributor":"Dennis, Miller"},{"type":"author","contributor":"Allen, Ed"}],"identifiers":[{"id":"978528641"}],"name":"before title test","publicationType":"Journal","subjects":[],"coverageStatement":"","customEmbargoPeriod":{"embargoUnit":null,"embargoValue":0},"isSelected":true,"managedEmbargoPeriod":{"embargoUnit":null,"embargoValue":0},"packageId":"123355-2867674","packageName":"carole create a custom package - 5","url":"","providerId":123355,"providerName":"API DEV CORPORATE CUSTOMER","visibilityData":{"isHidden":false,"reason":""},"managedCoverages":[],"customCoverages":[{"beginCoverage":"2017-04-30","endCoverage":""}]}}}

Response
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