When I traded my 2015 in for an '18, Ford disconnected my 15 from MFM. I got a message on my display telling me so the morning of the day I picked the new one up. If try pulling the fuse to reset as suggested and if that doesn't work, call Ford.
I was going to buy my 2015, but with the deal I was able to get on the 2018, I just couldn't turn it down. Upgrade from SE to Titanium, few options to not missing much if anything, monthly lease virtually the same.