Do not enter a tax amount in this line

What causes this issue?

The total of the G/L account amounts that are not tax-relevant is
displayed in a line with tax code " ". You may not enter a tax amount
in these lines.

System Response

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

How to fix this error?

Delete the tax amount in this line.

Error message extract from SAP system. Copyright SAP SE.