Old contract

Good morning

I update my contract on the 28 May 2024 online, a lady called me and go through my datails, I received the fone 1 and half week later. The time I must paid my first payment it was dubble. Then I find out that that fone they put on as a new contract, I ask them to cancel the new contract but no response and no one can help me. now it cost me a lot of money. Please help me.