They could also be out of stock, especially if they are dumb enough to be dropshipping. Suppliers for dropshippers are notorious for running out of product without notifying their sellers.
And that means, if you find other sellers who have the same items, they are also out of stock.
Dropshippers don't realize that they have dozens if not hundreds of competitors advertising in the same place.
Anyway. Not your problem.
If you are asked to agree to a cancellation, you are allowed to refuse.
If you do not get the item you can Report the seller for non-performance.
However, calm and factual feedback and appropriate Detailed Seller Ratings are your most effective tools. The normal DSR is Five Stars the lowest is ONE. (No stars is a free pass).
But before you go medieval on him, does the seller advertise that he ships to Canada and was the shipping fee you paid the fee to Canada? If not, he can Report you as an Unwelcome Bidder.
