New Contract Not Active - Incorrect Service/Bill

Help

My contract expires shortly and when I logged into my account I was offered different options.  I selected an option and agreed a new contract that should have gone live on 10th March.  I received confirmation via email of the new contract and left it at that. 

Today I received a bill for far in excess of the price agreed and I also noted my services hadn't been changed as per the new contract.

I have called and got nowhere.  Told wait a few more days, told I need new equipment - None of this is true.  I asked to speak to a manager but they are all busy and will only tell me the same thing apparently. 

It seems every time you interact or make changes things go wrong and it's always an uphill battle to get anything sorted.

I honestly do not know what to do anymore and it looks like I am not the only person this has happened to.