Endless calls to sort out problems , did not load my paid upfront airtime

I have had the worst experience with Cell C . From the start I ordered an upfront per month contract and they linked my Id number with someone else. Then they took a debit order and then stopped it . I then paid manually . All of that I could deal with. I have paid my account 2 months up front. They still have not loaded airtimethat I have paid for . I have called every 2 days written on Facebook and gone into the store . Spoken to mangers supervisors etc and everyone has a different story . From its loading, its execulated , they have changed the package and put me on a fiber package * without my permission apparently * each person telling me it will be sorted out . I have had to load extra airtime which has cost me a fortune . I have had enough . How many times must a person phone to get something they paid for .