HOW DOES A FROZEN ACCOUNT GET HANDED OVER TO DEBT COLLECTORS

I was a Member of Virgin Active in 2019 before i went on deployment my account was up to date and i contacted them to freeze the account in 2019 since i went on deployment. That was done for some reason i have never received any correspondence from Virgin Active that the Account was reactivated again and that am liabletopay for something that I'm not using. Now from a premium of R280 all of a sudden my account is handed over to SSDA for R3600 that contacted me via email once in January 2020 and then when i contacted Virgin Active to send me the contract and statements till this day 27/09/2021 no feedback on my request neither did they inform me of anything. The call records i requested from them where i made the arrangement to freeze the account was never given back to me now am receiving endless calls from SSDA to pay an account that was never in areas and for the matter it was frozen. Virgin active failed to communicate with me and instead handed me over to debt collectors who put me on a default why I would like to hear from them. Why my emails and calls never been responded to? Poor and unprofessional service and actually they must clear my name from that SSDA I'm very unhappy