https://ircc.canada.ca/english/helpcentre/answer.asp?qnum=1468&top=10
Can I lose my permanent resident status?
Yes, you can lose your permanent resident (PR) status.
If you haven’t been in Canada for at least 730 days during the last five years, you may lose your PR status. See Understand PR Status.
You may also lose your PR status if you:
become a Canadian citizen
give up (renounce) your PR status
become inadmissible to Canada
Permanent residents don’t have the same protections and privileges as Canadian citizens do. If you commit a serious offence as a PR, you may have to leave Canada permanently.
https://www.canada.ca/en/immigration-refugees-citizenship/services/new-immigrants/pr-card/understand-pr-status.html
Understand permanent resident status
Permanent residents (PRs) of Canada must carry and present their valid PR card or permanent resident travel document (PRTD) when boarding a flight to Canada, or travelling to Canada on any other commercial carrier. If you do not carry your PR card or PRTD, you may not be able to board your flight, train, bus or boat to Canada.
It is your responsibility to ensure that your PR card is still valid when you return from travel outside Canada, and to apply for a new PR card when your current card expires. If your PR card expires, it does not mean you have lost permanent resident status.
A permanent resident (PR) is someone who has been given PR status by immigrating to Canada, but is not a Canadian citizen. PRs are usually citizens of other countries, while some may be stateless persons.
When refugees resettle in Canada from overseas, they become PRs through the Government-Assisted Refugee Program or the Private Sponsorship of Refugees Program.
If you make a refugee claim in Canada, you don’t become a PR immediately. To become one, the Immigration and Refugee Board must first approve your claim. Then, you must apply for and obtain PR status.
You’re not a PR if you’re only in Canada for a short time (for example, as a student or foreign worker).
The permanent resident (PR) card
Your PR card proves that you have PR status in Canada. If you travel outside Canada and return on a commercial vehicle (like an airplane, boat, train or bus), you must show
your PR card and
your passport or refugee travel document
If you’re traveling outside Canada without a valid PR card with you, apply for a permanent resident travel document (PRTD) before returning to Canada by commercial vehicle.
If your PR card was lost, stolen or damaged, apply for a replacement PR card.
How to properly dispose of your expired PR card
Destroy your old PR card by cutting it in half before disposing of it so you protect your information and privacy.