Cannot reproduce on snapshot. Just Lotus: https://bugfest-lotus.int.aws.folio.org/

1. Go to Inventory

2. Find an Instance record with Source = MARC 

3. Go to Actions > Add MARC holdings record 

4. Create a MARC holdings record 

5. Save > Expected outcome: MARC holdings record created 

6. Edit the MARC holdings record 

7. Hit Save

Expected outcome: Successful save 

Actual outcome: 500 error message (see below screenshot) 

I cannot reproduce this issue when I create a MARC holdings record via Data import.