I have been using Koodo Prepaid for a couple of years with a Blackberry (Micro-SIM). I recently bought an unlocked iPhone 5S and a new Koodo Prepaid Nano-SIM.
I inserted the Nano-SIM into the iPhone, then logged into Self Serve and was able to change the SIM card using the "Change SIM Card" page. My iPhone now has service, while my Blackberry does not. All good!
My question is: can I leave the old SIM in my blackberry and switch back and forth between the old and new SIMs on Self Serve?
When I try changing the SIM on the "Change SIM Card" page back to the old SIM number, I get the error "SIM card number is invalid or already in use."