Something is seriously wrong with this picture:
- If you landed at 3 and left for 17 years, you should not have been able to re-enter Canada as a permanent resident. If you were allowed in, it was only because they did not know you were still a permanent resident. (If you have information that contradicts this, you should ask for clarification from an immigration consultant or lawyer. For example: if you were allowed to maintain your status for humanitarian reasons.)
- Not remaining in Canada at age 20 in 2010 almost certainly doomed you to losing your status. Had you stayed in Canada for over 2 years at that time, you could have kept your status by applying for a PR Card some time in 2012 or 2013.
- Given that you were allowed to return to Canada in 2016, it seems as though you are not a Permanent Resident. You should look in you passport to confirm this: is there an entry stamp?
- Based on the information provided, you are not eligible for a Permanent Resident Travel Document or PR Card as it sounds like you do not have permanent residence status in Canada. However, if you have omitted crucial information, we could be wrong about that.