You may want to try a different protocol. Wireguard is about the best but you can read up on it here>>
5+ VPN Types & Protocols (And When to Use Them) | IPVanish.
My 2019 Shield Pro has no issues at all and has all the latest updates. 'Droid 11 is fine. I definately would not take the drastic measure of reflashing your device. IMHO it isn’t necessary.