Internal error: Error writing to table &1 in function module &2

What causes this issue?

An unexpected error occurred during an insert to or update of a database
table.

System Response

The system cannot continue processing.

How to fix this error?

Note the exact point of the program termination and what led to the
termination, and send a customer message to SAP.

Procedure for System Administrators

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Error message extract from SAP system. Copyright SAP SE.