Disconnects and trouble reconnecting usually point to a phone or bandwidth issue. I will say that I'm seeing a lot of rumblings on the Net regarding the new iOS 26.x beta updates and CarPlay. With that said, there are some best practices when it comes to reliable connections:
1) 9 times out of 10, a phone restart will resolve your issue.
2) Wireless CarPlay/Android Auto takes a LOT of bandwidth - if you are tethering anything to your phone's hotspot (Rivian, other passengers, etc), don't. Keep it off.
3) If you do need to keep your phone hotspot on, use the wired CarPlay/Android Auto feature: Unpair/delete the Aautokit/Autobox connections from your phone and attach a quality data cable (not a gas station charging cord) between your phone and the single BLACK USB port on EV Play. A lot of customers prefer the wired connection due to its speed to connect and reliability.
4) If you don't need them on, turn off your Rivian WiFi and hotspot, as well as the EV Play (Android) WiFi. If you need those on, visit the 192.168.43.1 admin page again and try changing the WiFi channel to another 5ghz one. Do NOT choose a 2.4ghz channel.
5) Some folks do better with Software vs. Hardware decoding (AA/CP app>settings>Decoding Method). If you choose Hardware, make sure Resolution - the setting under it - has 2362 x 1218 selected.
If all else fails, reach out to me and we'll try and troubleshoot.