Virgin Active services

I had a membership which the contract was ending 2016. I then called them not to renew. There were no deduction after. November 2019 they sent my sister a message that I am owing, which I called wanted a clarity that I never change my contact, email address and banking details. Why they waited almost three years and receive a call from attorney. When I call their call centre on the 24/02/2020 this lady said they tried to contact in 2016 for me to give a go ahead to deduct. I told her but they have been deducting for two years why they needed my permission.