Income tax refund of deceased assessee to legal heir

Dear Sir,

My father expired in october 2016, leaving behind a registered WILL. In the WILL in one para he clearly defined his heirs after his death. In another para of WILL he clearly mentioned theat any income tax refund it will go to my son Ashutosh Kumar (me).

As legal heir I filed his income tax return for AY 2017-18 and it was assessed also and U/S 143(1) assessment order issued. While filing income tax return I mentioned my bank account details, since his account was closed by me. 

CPC Banglore send me a letter stating mismatch of bank account. They asked Assessing officer of my jurisdiction to verify the legal heir. AO says it is not our jurisdiction.

Please guide me how to get refund.

Thanks

Ashutosh