IGST CGST AND SGST INPUT

Dear Experts

we have sufficient input balance in CGST and SGST ledger for do setoff against out put CGST and SGST.

In the month of sep we paid RCM charges for import of services. This too accumulated in the credit ledger.

my query here is shall we claim refund of IGST we paid for Rcm services without adjusting out put CGST and SGST and its compulsory to exhaust IGST against out SGST and CGST.

we are regularly getting import of services. For this we are paying IGST .
My consultant told me that we needs to exhaust IGST input against CGST and SGST output.Due to this SGST and CGST input amount added in credit ledger.

kindly advice,shall I get refund the amount accumulated in CGST and SGST ledger.