info. about gst filling

dear sir..
i m a service provider and have a transport franchise..
in the beginning of the frenchise they demand me GST no.
so i have done registration under GST on sep. 21st 2019.
but because of misshaping they not receive my gst no. for 4 Months nd will be pay commission without GST charge.
hance at the time of filling return from 21st sep to 31st jan. income will be show online... but GST not filed..
according to the company they will not give gst because of financial yr closed.
plz suggest what i do for that GST. amount which is dew...