No entry in check number field

What causes this issue?

You want to make the payment by check, but have not specified a check
number.

System Response

If a posting is to be carried out, an error message is issued.

How to fix this error?

Specify a check number or deactivate the field for check payments in
<ZH>Payment specifications</>.

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.