Glide bills

Hi I live in a 5 bedroom student house and we are having problems with the company glide. So we started a tenancy at a new property in July, and properly moved in, in September. We were advised to get our own bills sorted, so we opted for a bills company which split them for us (Fused Bills). We started paying this in August as we weren't there from July-August. This has been completely fine and we're still paying them now. However, on Oct 12th I was contacted personally by a company called Glide (they had my details only as i got the quote for the 5 person house). They said that we were with them
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and we were on a flexi contract, which we didn't sign but has apparently rolled over from the previous year. They kept barraging with emails on the following weeks and have called and text me saying I owe them £91, today they have text me saying if this is not paid they will take legal action