upgrade without consent

Good day

I trust you are well

About a month ago someone called me in regards to upgrading my *** number. I declined the offer as I am happy with a month to month at the moment , I advised that I would consider an upgrade in the near future.

they have gone behind my back and upgraded me to a data package , 36 month contract , i have called and tried to sort this out. I was advised that I would receive feedback in 7 working days , 7 working days have come and gone. I would now like to upgrade my cellphone and i can't.