Export length for field & was set to &

What causes this issue?

The export length for field &v1& must be at least &v2&. It was set to
this value. You can overwrite the value with any length greater than
&v2&. The minimum length of &v2& is calculated from data element &v3&.

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?

Error message extract from SAP system. Copyright SAP SE.