I will be billed for a month

I took out a contract with Mweb 3 years ago. The contract was for 12 months. After that according to the salesperson it will be on a month to month basis. I asked the salesperson when I want to cancel do I give a month's notice he said No. It will be immediately cancelled because of the month to month basis

Today I wanted to cancel for month end as we are tenants and the landlord sold his house and ask if we can be out month end. We were not told about the house being sold.

Customer service told me I must give a month's notice. I told him we moving out the 27th April and we want it cancelled. They said they cannot do that they will still bill me for a month of not using it. And we won't be in the house while it's on here.

So why did they salesperson tell us we can cancel anytime and no month notice is needed.