As long as I have been collecting on AP I also didn't have any problems with missing miles. Since my switch all miles from airlines other than AC have been credited and NONE of the five AC flight segments I've flown have been credited correctly.
This is the last response I got from AC Customer Relations on this matter:
Thank you for your further email.
We regret your continued disappointment, (my name), and assure you your concerns have been reviewed appropriately.
Our considered response has been provided and further discussion will not alter our position. As such, we will not respond further communication on this matter.
We regret we were not able to conclude this matter to your satisfaction and trust you will recognize Air Canada’s position.
Coincidence? What are the chances?