VIRGIN ACTIVE NOT CANCELLING MEMBERSHIPS CORRECTLY

After a friend and I went to sign up for a new membership today, I finally figured out how Virgin Active catches people when they cancel. It turns out we were both owing money to Virgin and had both been handed over to lawyers. When I signed up around 2 years ago, I was the payer for myself, my husband and my daughter. When I moved medical aids I cancelled. Instead of cancelling the whole membership (which me being the payer it should be obvious they are all cancelled), they cancelled only my membership. They then ran up an account for a full membership for both my husband and daughter for a further 2 months. I think this is scandalous and I need Virgin Active to reply on why they are doing this as this seems to be *****. My friend was joined via her mom (the payer) and when her mom cancelled the whole contract, they left her on the membership and ran a bill up for her. Sounds sneaky! Virgin Active, what is your angle here? Why are you ripping people off?