HANA trial authorization issue

Hello experts,

I am trying to build a oData service in hana trial system.

Currently I am in JN4 with DB user DEV_xx...

Via hana studio, i can preview the data content of table in EPMSAMPLEDATA.SNWD_BPA.

So i create xsodata to expose the content in this table, businessPartner.xsodata.

Then accessing the URL https://s2hanaxs.hanatrial.ondemand.com/xxxxxxx/services/businessPartner.xsodata is working.

But when i try to access the content via https://s2hanaxs.hanatrial.ondemand.com/xxxxxxx/services/businessPartner.xsodata/businessPartner

There is an authorization error.

Service exception: insufficient privilege.

exception 1: no.71000258 (ptime/query/checker/query_check.cc:2547) Not authorized NO exception throw location recorded. Stack generation suppressed.

The strange thing is, i can access the table content via HANA studio, but i can not access it via oData services.

Could you help me out? to see what i have done wrong？

Thanks a lot!

Regards,

Charlie