I doubt the dealer will do anything at this point and if they did they'll likely charge you. You can always ask though. If you want to update the map it's real easy and takes about an hour of your time. You don't need to sit in the car the entire time, just in the beginning to get it started. They suggest you either hook up a battery charger or leave the car running. Map updates are running $99 + the USB drive through the end of the year. My dealer doesn't stock them nor seemed very interested in getting it so I ordered online at https://www.mapnsoft.com/us/kia.
I've had this happen several times. I usually don't notice until I'm already moving and the first time it happened turning the car off and on didn't fix it. I can't remember how I got it working the last time I noticed it but I think I held the power down for 10-15 seconds or something. There's also a reset button on the radio that would probably work if you're not driving and at a red light or something.
I have had my 2013 Sorento into the shop for this same problem. The dealership return it as "couldn't duplicate the problem". But it happens all the time when I am driving the car... But not my girlfriend... But, I figured out what is causing this (for me).... If I start the car, apply the brake, shift into reverse before the radio powers up, the Kia logo hangs on the stereo. How long it hangs is intermittent.... But I can reproduce this on queue everything,e now... It's off to the dealer with my new found cause and effect...
Its happened on my UVO non-navi system as well, only a few times, like its froze or something. Takes a minute then works fine, but If it ever stays suck, take it to the dealer and have them check it out.