There is error of non-unique id number
Please show BP that is used by POST /asset_library/ endpoint
It can be sequence issue if previously there we inserts with ID using SQL Exec or DB Editor.
Since that’s a standard DB block, the only issue can be is: you previously inserted data via SQL Exec or DB Editor directly to the database with id field set in your request and PostgreSQL automatic sequence has no information about that.
If thats the case - try to update sequence using any available method or ask our team to do that as the last resort if no other methods worked.