A default value has already been set for manual taxation

What causes this issue?

You have entered a default value for automatic taxation. However, since
a default value already exists for manual taxation of the meals and
overnight fees, it is for not possible billing reasons to give both
taxation types a default value.

System Response

The system cannot accept the new default value.

How to fix this error?

Check which taxation type is valid. If taxation is automatic, first
delete the default value for manual taxation and then re-enter the value
for automatic taxation.

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.