PUT Method Not allowed Error on SAP EP Portal

Dear All,

We have integrated SPAUI5/FIORI launchpad to SAP EP and trying to run the custom SAPUI5 application. But we are facing below issue,

1. While running service /sap/opu/odata/SAP/ZIMPTMP_SRV/IMPORTUPDATEALLSet(MergeId='18KSJ00020') (PUT method) from gateway, it working perfectly fine.

2. Same oData Service I am trying to call from SAPUI5/FIORI application hosted on SAP EP, but giving me attached error.

Please help.