You must have permanent resident (PR) status in Canada, have no unfulfilled conditions related to that status, and your PR status must not be in question. This means you must not:
be under review for immigration or fraud reasons, or
be under a removal order (an order from Canadian officials to leave Canada), or
have certain unfulfilled conditions related to your PR status.
You do not need to have a PR card to apply for citizenship. If you have a PR card, but it is expired, you can still apply for citizenship.