Error when writing IDoc status: Invalid status

What causes this issue?

The status record of the IDoc could not be written in the previous
step because the status value was invalid. This error can only result
from a program error.

How to fix this error?

If the error was caused by a standard function module for application
input, please contact SAP.
Otherwise check the function module called.

Error message extract from SAP system. Copyright SAP SE.