Luckily you have a 2015 and can do a soft reset on the uconnect with right button press combo. Try that process.
My 2018 Trackhawk did this same thing and with the newer Panasonic unit they did away with the soft reset and I had to go to dealer to have it reset. I tried unhooking battery several times and people on here kept telling me eventually they will just come back to life. I gave mine 8 weeks of daily driving before I went to dealer