Canada has its own stores on most platforms. Here is how to buy the right CAD card and avoid US-card mistakes.
Canada and the USA are neighbours, but on most platforms they are separate stores with separate currencies. A Canadian account needs Canadian dollar (CAD) cards for PlayStation, Xbox, Nintendo, Apple and Google Play.
Buying a US card for a Canadian account. The code looks valid but the platform refuses it with a region or country error. The code itself is not broken: it just belongs to a different store.
Steam uses the Canadian dollar for Canadian accounts. Steam cards from other regions are usually converted into CAD, but regional limits can apply. Check the Steam card page for the regions listed.
If a card is not available for Canada at the moment, it is better to wait than to buy another region that will not redeem.