Material number can only be &2 characters long

What causes this issue?

The given length of the material number (&v1& characters) is longer
than the total length of the material number (&v2& characters).

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?

Correct the material number.

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.