Go through the below solution:
If the reconciliation account is tax-relevant for down payments, you always have to enter a tax code. Setting 'Tax code is not a required field' in the master record remains ineffective.
You can change error message FS222 into a warning message.
In addition, you have to set indicator 'Tax code is not a required field' (SKB1-XMWNO) in the master record of the reconciliation account.
Note 755623 - Down payment processing
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