Stopping scam registered to deduct from my account
I received this text twice on my mobile “FreeMsg: Reminder. You are subscribed to MyContent for £4.50 every week from Nextgen Ltd until you text STOP to 64005. HELP? 02037403517“. I ignored it the first time as if it were spam, however it turns out I’m actually being charged £4:50 per week. I phoned the telephone number but it was just a message service and they wanted more of my details!! NO WAY!! I phoned BT but they advised they could not stop it as it was a subsctiption service I had signed up to. I had not and do not recognise this firm. What service are they offering? How could they do it? How did they get my permission? I just want this to stop and not happen again. Any help on how to do this without texting back that number or being conned with this scam again?