Error executing enhancement & (function exit &)

What causes this issue?

Component &V2& (function exit, function module) of enhancement &V1& was
processed. Function module &V2& in function group &V3& was called.
Export data was not provided in the correct way in this function module.

System Response

Programming in this form leads to program termination and is not
permitted. The program termination was recorded and issued in this
message. You cannot continue processing.

How to fix this error?

Check the programming of function module &V2&, function group &V3&. Note
the documentation on en error processing for enhancement &V2&.
As this is a customer-specific enhancement of the SAP system, contact
the person responsible in your company, if necessary.

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.