Pritunl client is not connected to the internet

Hello!
I have been using pritunl on my VPS server for a long time. Recently I switched to another VPS, configured everything as before and faced the following problem: all devices successfully connect to the server via OpenVPN, but half of the time the Internet is simply unavailable, despite the fact that the server is alive and no errors are displayed anywhere. What could be the problem?

Check the steps including testing MTU in the client debugging documentation.