Cancellation process

On their website: "You can place your notice of cancellation one calendar month before the date of cancellation".

So yesterday I tried to cancel which was the last day of Jan, and wanted my service cancelled at the end of Feb, which by definition is one month's calendar notice. But I didn't get any help from them yesterday. They said they were transferring me to their cancellation department but they didn't. Just left me waiting on the chat for 2 hours. Then when 5pm came around, boom, no help at all.

Now today on live chat they said even if I did give notice end of Jan to cancel at end of Feb, my last payment will be 1st April.

So end of Jan I gave my one calendar month's notice, but my last payment will be on the 1st April?

Been a customer for many many years. Please clarify this for me.