My contract is ending soon, I have two and do not want to re-new the one that is ending. How do I stop automatic renewal - do I have to cancel in writing/e-mail? If so wher can I find the address?
I would additionally recommend considering asking the service provider to move the SIM to PAYG instead if you would be interested in receiving calls on that number after the end of the minimum term of the contract.
Just by means of advice on terminology, mobile contracts in the UK don't "expire" or need to be renewed - they are ongoing contracts with (typically) a 30day notice period and a minimum term.
I see you've already been given the link to EE's guide on giving disconnection notice - but you can do this by calling C/S on 150 from your mobile, and asking the agent for a standard cancellation.
If you choose to retain your number on a PAYG basis, then you need to request this during the same call.
But you can not call from a mobile broadband device. Also the hours of chat and call centre are designed only for people who do not actually have a job, seriously, 8 to 8 and not before 10 on a weekend. This is 2021 not 1960. EE are not designed for this century.
