Income tax refund

I have filed a return of my wife for the AY 2016-17 last month and return was processef and I received 143(1) which says refund is processed and date of order is 24-03-18 . But till now I have not reveived the refund.My Query is that she is an NRI now (AY 2016-17 she was Resident) and our old Joint a/c is changed to Savings a_c in my name as her status is changed. I have given the bank ac in my name for refund purpose as she doesnot hold any Local A/c in India. Is that might be the reason for delay in refund.In this case how can I claim the refund