Customer number '&' of exchange partner '&' does not exist.

What causes this issue?

This is a system error

System Response

Abnormal termination

How to fix this error?

Check vendor and customer master data of the exchange partner '&V2&'
and contact your systems support.

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.