I was talked into signing up with Future Comms (future-comms.co.uk) who cold-called me to change my mobile contract to them, via 02, rather than EE. I have a small business (only me!) and it's a business contract. True, the 4G network is better for my area. This company seemed to be a marketing set-up for various telecoms companies, so I assumed anything I signed would be with 02 and didn't think it might be a problem.
They sent an email whilst I was on the phone to set up the direct debit