I know its frustrating but keep calling, that is what I had to do for my daughter as her doctor is through there. Once I got ahold of them, I was able to get an appt fairly quickly.
I also would encourage you to use Qdocs, depending on the issue! I have had a lot of success with using Qdocs to tie us over until being able to get an appt.
https://qdoc.ca/
Hope this helps