Extending OData Service of Manage Supplier Line Items, Filter's group Label not work

[MassimoX]

Hi Community Members, i have some problem Redefining a standard OData Service FAP_VENDOR_LINE_ITEMS_SRV(Manage Supplier Line Items) . 

I have reDefining a standard OData Service for add some standard and custom field, but after activations and /generation the label for Filter group was disappears .

I have reDefining a standard OData Service without problem, except label for Filter group.

i don't understand the problem , someone can help me?

Thanks.