Undue debit order and arrears crucification

My account is not in arrears cause I don’t have an account with Virgin Active cause I cancelled my subscription in January. I am so upset with Virgin Active. I have been repeating myself since January and yet they keep debiting me and I keep reversing. Now they tell me I owe them, I am in arrears. In the call on 1st March I requested to speak to a manager and she promised to review all the calls and call me back with a resolution. Even to date she hasn’t called me, in this call I specifically asked that the harassment calls stop because I am tired of reiterating my cancellation. I have received two of the harassment calls after the one of the 1st March and none with rectification. Before this I had been with Virgin Active since 2012, almost 9 years, why will I default now after all this time?