Mahanagar Gas — bill issue assumption bill

Address: Thane, Maharashtra, 401107

Bp no - [protected]
The bill that recieved had assumption amount and meter reading which i informed through message, but no reply from mahanagr gas, and now they want to pay me the panelty as well.
So now i will have to pay assumption amount + penalty, atleast they should habe sent a message or intimation that your bill will be ajusted later. I was waiting for their reply after getting assumption bill and now they are saying to pay penalty along with assumption bill.