Wow, 12 week is an extremely long wait.

To contact and cancel the order, you would have to contact the webstore directly. You can send an email with the detail to this koodo.webstore@koodomobile.com.  Someone there should be able to cancel the order for you.

My iPhone 13 order just got cancelled.. how long till the refund is returned?  I didn’t even contact them to cancel it just canceled on it own. 

Also how long does it take for my tab balance to be reversed?

If they cancelled your order, then it shouldn't take too long.  Especially the phone is not shipped yet.

I would contact their webstore and ask them why they cancelled your order.  Is it because of supply issue or something with your account...? They need to explain that to you.