Vodacom is bad

I am sick and tired of vodacom. Opened a contract with them two years back because of changing employers I missed few debit orders but at the same month I go and pay cash at the vodacom store almost double the amount. My contract ended I asked them to renew they said I cannot afford they declined me I left them them today I receive a statement that I owe them more than double the instalment that I was paying. They have best network but if they treating people like I move to another network