Expired Contract at Vodacom still being charged

Vodacom after my contract expired still charge me. The law allows them to have a hidden clause in the fine print that allows them to continue charging unsuspecting clients. Any ways I paid them finished as I found out I was blacklisted when wanting to buy something on credit. But this is not the thing. The thing is they quick to take your money however when it comes to give you a settlement letter they are nowhere. I posted them on Hello Peter twice. They sent an automatic message private response a consultant will make contact with me. I am still waiting on a consultant to call me. Why does the law allow phone companies in the first place a clause that says we must do something to have our Contract terminated. It should happen automatically. If you rent a place the contract expired when your time is up. It does not continue. You have to sign a new contract if you want to keep renting. Why cannot this law not apply here. PHONE COMPANIES GET AWAY WITH MILLIONS.