Interest on Gst

Dear Experts
We have Deposit Rs 5,00,000/- as Gst Amount on dated 20/01/2018 in respect of December 2017 GSTR-3B and the same amount is credited in our cash ledger but we could not file our return on time, we filled the same on dated 20/03/2018 So you are requested to please suggest that we have to pay interest for two months or not.
plz suggest with sections