Poor management and poor service

They sent me the account of which i have to pay my Vodacom credit installment and then i payed i even sent them the proof or payment via whatsa and email and still they ddint respond and now i was supposed to pay the last installment next month, and now because they didn't clear that installment i payed via eft i am left with 2 months to pay here is my ***. My phone number is ***