Very bad

I had a 3 year contract with vodacom my contract ended in July 2026 The plan gigs was 1 Gig the give me with the phone and tablet I took they never let me know my contract was finish in July so I left it here in August they phone me I was in arrears I paid them R1450 to get up to date remember contract is finished im paying for 1 Gig and so I send them a letter threw my portfolio manager that im done with them!!! Today with my astonishment they Debited R2100 on the 28 of September for 1Gig!!! Daylight robbbery