I recently visited my mom in Canada and found out that I still have Canadian Permanent Residency which I had around 43 years ago.I completely forgot I had it since I already am a US citizen. No one ever notified me if it expired and I can't find my permanent resident card. Now the immigration officer wants me to renounce my permanent residency. What are the chances of me still keeping it without fulfilling the requirements? Are there pros and cons in keeping it? The immigration officer said that if I don't renounce, I won't be able to go back in to visit.