It is most likely impossible to reinstate your PR after so long, but there are many considerations to take into account to give you a clear answer. I strongly suggest a consultation with a Canadian lawyer so that you can look at your options.
How can I reinstate my permanent residency in Canada?
I received Canada PR in 2007. I stayed in Toronto for two weeks then returned to my country. Is it possible to reinstate my PR? I only stayed 14 days in the country in 2007 and after that, I never returned to Canada.