Gst return filing of hotels in oyo

Dear All..

Let me explain the case in detail.

Let the name of the Hotel be 'X'.

X is now running associated to OYO. Room booking is done only through OYO. For those rooms booked through OYO (Here only OYO booking is there) 'X' should give 30% of Rentals to OYO. Invoice is generated by OYO. 'X' is not giving any bill. OYO has told 'X' to give X's bill in case the party asks for. Payments from 70% of clients are received by ' X' and balance by OYO. Who should file GST returns? If OYO should fiile then how 'X' should file his GST Returns to show his 70% income? What about the GST collected from clienrs by 'X' and OYO? 

Thanks in advance