****** prepaid data by service provider

I was on both prepaid and contract, and yesterday the 02 May 2024 purchased a R199 20 gigs valid for 1 month and mtn stole it from my account reason is my contract ended and everything including balances which I already paid for were forfeited. Then my question was why did I loose my prepaid data, they had no reason to that. If you were about to take any contract with this company stop and play far from them. Their client service is really bad.