You created an EC by partner development on Opportunities Quick Create and defined a default value for a field in this EC. But only the restrictions are working and defaulting is not.
SAP Could for Customer.
Defaulting only works in case of create or create with reference scenarios. In case of read defaulting will not work.
In your solution, is needed change the import in order to trigger a create, so defaulting shall work properly.
CLR, Code List Restrictions, CLR PDI, Default Value PDI , KBA , AP-RC-UIF , C4C UI Framework , How To
SAP Cloud for Customer add-ins all versions ; SAP Cloud for Customer core applications all versions