Gst refund

Dear Colleagues,
I have GST refund query regarding GST paid with payment of IGST.
Exporter has filed all GSTR 3B and GSTR1 till the date. They have exported the goods with payment of IGST in July 2020.
To get this refund there is requirement to file GSTR 1 with mentioning correct details of shipping bills. Once the same is being filed the icegate portal will check the details and accordingly credit the IGST amount in exporter's bank account.
In my client's case the same has been done but they did not receive the refund till the date even though the status of invoices transmitted and as processed from table 6A are matched.
Please suggest or advice what should be the course of action to do in such case.
I am grateful for your help and support!