Aual return 2017-18

Venkatesan Ramanujam (123 Points)

07 December 2019  
we have filed anual returns for the year 2017-18. But for the month of August 2017 we have not filed GSTR1 but filed GSRR3B and paid the Tax due. Because of non filing of GSTR1 the party whom we have sold unable to use the input (they have used but have to pay that used input when filing their annual return)
we have paid the Tax but again we have to pay the sellers,!
Please guide me what I have to do whether can I file GSTR1 for the month of August 2017.
Yours,
R Venkaresan