No authorization for displaying vendor; see long text

What causes this issue?

No authorization for transaction MK03.

System Response

You cannot access the requested data.

How to fix this error?

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Procedure for System Administrators

If necessary, include an entry in the user's authorization profile for
transaction code MK03.

Error message extract from SAP system. Copyright SAP SE.