Hi there, @nlad747! I see you’ve tagged both Android and IOS mobile device types in your post. If you have the option to test Ring app functionality on each mobile device, this can certainly rule out many mobile device factors. Please ensure there is not a vpn enabled on either.
With you network resources being sufficient, I recommend also checking on your device RSSI reading in the Ring app. This will let you know if the signal is experiencing any interference. Feel free to let us know how this goes! 