Unfair billing with no service

Telkom has billed me an amount of R672 which I paid and sent proof of payments (which they acknowledged) but they still went ahead and blocked my cell phone contract cause apparently they are now tracing the payment . A week later They then debited an amount of R1111.40, which I called and made a query and I went in store for them to rectify thier mistakes but all I am getting is *********** agents who cannot help me. I am now sitting with a blocked phone number yet I am paying for thier services