Why can't users edit contacts even when they're the owner?

The users might not be synced with the Oracle Applications security database tables. Here's how to fix the issue:

1. Run these scheduled processes:
   • Synchronize User GUID. This process resolves invalid and missing user global unique identifiers by synchronizing them.
   • Import User and Role Application Security Data. This process imports user and role data from LDAP and stores it in the Oracle Applications security tables.
2. Next, navigate to Tools > Sales and Service Access Management.
3. Navigate to Object Sharing and select the Contact object from the drop-down list.
4. For the access group that the users are in, set Access Level to Full.
5. In the Object Sharing Rules page, select Actions and publish the access group rules.
6. Navigate to the Monitor tab and run the scheduled process, Perform Object Sharing Rule Assignment Processing.