Sometimes no notifications Doorbell 3 plus

Hello!After pressing the ring, there are no notifications on the smartphone and chime pro. It happens randomly, once everything works fine, but many times I don't get any notifications. I am currently using the second device because due to these problems the first device was found to be defective and replaced. Both devices are affected by this problem. All tests are satisfactory, the signal strength for the devices ranges from RSSI 42 to RSSI 44. Does anyone have similar problems? I suppose this is a problem with Ring servers.