Billing is performed incorrectly by Discovery and the members benefits are suspended

On 18/05/2022 I was notified that incorrect billing had occurred on my medical cover contributions resulting in over payment from my employer.(this was the result of incorrect billing by Discovery billing department)I was advised that the outstanding amount would be recovered over a period of 18 months as from 1/07/2022. A few days later my medical cover was suspended. Up till date no debits have been performed by Discovery. As of 1 December 2022 Discovery performed an increase in contributions which now once again resulted in incorrect billing from my employer and recovering the full amount for contributions from me. I delivered communication of the incorrect billing to Discovery to which they have responded with a letter advising me that as from 09/01/2023 my health benefits have been suspended until the total amount outstanding was paid. None of this was by any default of me but entirely by the Billing section of Discovery.