SAP Netweaver gateway oData Service is running through direct link but not through portal

I have built an ui5 Application which is consuming SAP Netweaver Gateway oData Service,

When I am running the application from direct link, the service is working fine but when I am running it via portal, the service is giving me the Error "Invalid Key Predicate”.

Query:   /ZHNEWLEAVE_SRV/GetLeaveQuotaSet(Pernr='43',Awart='1001',Leaveno='',Trtyp='C')

Below is the  browser console error screen shot

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