It sounds to me that this could be a software issue. The only way for us to correct the issue was to "reboot" the car, by turning it off and back on again.
I asked my dealer to re-flash the software the first time it happened and they did not. This time, I asked Ford Customer Service to ask the dealer to do it. They told me they would. We will see....
Please keep me posted on your situation and I will do the same.