No new serial numbers can be entered for material & (&)

What causes this issue?

You are trying to create <GL:serial_number>serial numbers</> for a
<GL:material>material</>. It is not possible in this case as the
<GL:serial_number_profile>serial number profile</> in the
<GL:material_master_record>material master record</> does not allow
the creation of serial numbers.

System Response

INCLUDE 'KEINE-FUNKTION' OBJECT DOKU ID TX LANGUAGE E

How to fix this error?

Use the serial numbers already created in the system.
If this is not possible, contact your system administrator.

Error message extract from SAP system. Copyright SAP SE.