With item cat. &, inventory mgmt. of material must be value-based

What causes this issue?

Value-based <GL:inventory_management>inventory management</> is defined
in the <GL:material_master_record>material master record</>, but the
<GL:item_category>item category</> does not allow the material to be
included in inventory management.

How to fix this error?

Check whether you have entered the right item category;
If you have the relevant authorization, you can check the item category
using the Customizing facility:
<DS:SIMG.SIMG_CFMENUOLMEOMH4>Define external representation of item
categories</>

Error message extract from SAP system. Copyright SAP SE.