Poor service, communication and incompetence sales reps

Hi My contract was coming to end on 28 December 2021, so I received an email that I should pick a new contract going forward then I call around the 7th after paying for December 2021 to update for the 28 of December but the consultant suspected my current paid for subscription and pro-rated me of which I logged a complaint and I was promised a call to fix the issue but that never happened, when I called their sales number the was never a response, so I waited for the January debit then I was over charged because of the pro-rata instead of paying R479, R630 was debated.

How is a paid for contract suspended, when I was calling for the new contract?

This is happening the second time it happened even in December 2020 when I took a new contract with them was pro-rata when I had already paid for December and kept to contracts running when I had called and canceled 1 and I never received my money back after numerous complaints.

I was expecting to pay R479 not the R630 that was debited