New contract, incorrect payment.

I entered into a new contract for tv and broadband package on 11/09/2024, I have a contract sheet which was emailed to me.

It clearly states initial monthly cost £69.99 per month, from month 19 it will be £156.00 per month. When I got the app and checked payments due it shows initial monthly cost £156.00, this is obviously incorrect. I’ve contacted helplines on 4/5 occasions with no success, on the last occasion I was told to email a manager with copies of my initial contract showing £69.99 per month. This was done immediately, I’ve since resent it twice, to date I’ve heard despite being told the issue would be resolved in 48 hours, this was done on 0/12/2024. 
I was told that if I paid the outstanding it would be sorted so I paid £185.00 to no avail. 
I’ m now receiving messages re arrears, and the consequences of not paying, no idea how to resolve the issue. !! 
If someone could advise I’d be grateful.