refund money

I filled return in the assessment year 2017-18 for the financial year 2016-17. The claimed refund amount sanctioned, but due to mismatch of my address change it has not given to the bank A/C. In the month of September 2017, regarding this an informnation & proforma of the filling of "refund re-issue" given by IT DEPT through e-mail to the person who sent my e-return, however unfortunately the person not intimated me at right time. The filled proforma of refund re-issue, dispatched by speed post on 14th March-2018, by me, which is too late. Till today IT Department did not issue the sanctioned refund amount into my savings account. Please tell me what I should do to get refund amount from IT department.