I took out Bonitas medical aid for my wife and 2 children

I took out Bonitas medical aid for my wife and 2 children. Never missed a single premium payment for 2 years. Everytime we had to use the medical aid for dr visits, casualties or dentists we ended up paying out of our own pocket as the "savings account " was depleted. This account was never replenished even though all payments was up to date. After canceling the policy and receipt of all payment being up to date and that I did not owe any outstanding payments, Bonitas handed me over to collections company ITC and now I am being harassed by ITC even after I have submitted all proof that all payments are up to date.