Debit order contract device unaware changes 😭

I will never recommend to anyone to buy any device from Vodacom (online contract) Their debit amount always changes, last time I tried several times to call them,they ignored until I wrote my concern here,they fixed the matter by that time,guess what? This month I've received my statement the amount again increased without any changes that I made😭😭 I totally regret because this is my second contract device that I bought from them, my colleague want to buy a new phone,I'll warn him not do the mistake on supporting Vodacom,I can't wait to finish paying this outstanding amount,💔💔💔 there's no peace at Vodacom 🚮