Day of sign up Gas meter reading was provided but still showing as estimated and it is way off

We signed over to Bulb on 28th September 2018. We provided both a Gas and Electricity reading - the Electric meter reading was correct and this is apparent on the account - but when this month we are being asked to provide meter readings - the gas reading from last month is showing as estimated and it is not correct especially when we provided the correct meter reading on that day, and your estimate is off by a lot and we have certainly not used that amount of gas in this last month.

If we put in the correct Gas meter reading now - it will appear we have used more gas than we actually have.

Would appreciate some help and advice on the next course of action as this would generate a higher bill that is not accurate.

Thank you.

I would phone Bulb, in the meantime it is likely as you are a new user that your gas is an estimate as your final /start readings have to be verified by a 3rd party and it can take up to 6 weeks.
As for billing you wont be charged more as your dd will remain the same and when actual readings are used it will balance out.