Virgin media scam

Can someone help me! I opened a sim only contract with Virgin media and cancelled it the next day. The guy on the phone confirmed that he had cancelled and would send me a letter in the post confirming. Anyways a couple of months go by and I am being told I need to pay my bill. I then call up saying what bill I don’t have an existing contract with you. At this time it was covid so I did not receive any correspondence after that. Then I started receiving letters saying I owe them money. I called in a few times requesting to speak to a manager or a supervisor. I would get the same reply that they are either not in  today or we will get someone to call you back. No one ever did and then now Virgin media have now sold my details to another company. I now have BW legal contacting me. I have written to the CEO, the complaints teams for virgin media all are ignoring my emails.  Imagine a reputable company harassing humans and trying to rob them of their money. Money which they do not deserve this SIM card was never activated I even asked from the goodness of my heart when I had cancelled do you want me to return it to your store. I have now been asked to get legal advice and that’s the only way out. So imagine I am expected to pay for a lawyer which would cost more than paying the money they would like to take from me for free. Such horrible people they may think they have won. But the truth always comes back to bite us. Probably why since covid they have had to close so many of their stores. I would honestly advise you stay away from this company the amount of negative reviews there are online about this company is horrific. I wish I never even entertained the idea of considering a contract with them.