Status "&" of material & does not allow external procurement

What causes this issue?

External procurement is not defined for the
<GL:material_status>material status</> of the
<GL:material_master_record>material master record</> you entered.

How to fix this error?

Check the correctness of the material status in the Purchasing data of
the material master record.
You can change the material status in the Purchasing data of the
material master record if you are authorized to do so.
If you do not have the relevant authorization, inform the individual or
section responsible for material master record maintenance.
Or contact your system administrator. The latter can check the material
status using the Customizing facility.
<DS:SIMG.SIMG_CFMENUOLMSOMS4>Define material status</>

Error message extract from SAP system. Copyright SAP SE.