Yeah, that's a pretty solid network since it's on ATT, though I will say that I switched to ATT from Consumer Cellular last year because of drops and such, even with a signal. And I switched to ATT and it's been more reliable, though that might be a function of changing phones. I was on an Android phone (Nokia -- fairly new with a new version of Android), and now I am on an iPhone 12. iPhones are much better, so it might be the switch to iPhone that improved my service and not going from CC to ATT.
Though I guess ATT traffic gets first priority over other networks on ATT towers. I miss the lower price of CC. I pay $80/month for ATT. The iPhone was free -- $12 per month but they credit $12 since I signed a 36-month contract with ATT.
I'd probably call your Hyundai dealer, and see if they have an update to the infotainment software. There is one you can download to a USB stick, but the dealer can probably do it for you also.
Also, are you using Carplay wirelessly or connected via the USB cable.