The default behavior for the Cato VPN Client is to connect to the PoP with a UDP tunnel using port 443. However, there are times where this UDP port is blocked (such as airports and hotels), and as a result the Cato Client can't connect to the Cato Cloud. When UDP port 443 is blocked, the Cato client automatically falls back to TCP traffic and attempts to connect to the PoP with a TCP tunnel using port 443. The client continues to use TCP traffic and doesn't return to UDP during the session. If you disconnect the VPN client from the network and then reconnect it later, the client tries to connect to the PoP with a UDP tunnel.
To force all Client traffic to only use TCP traffic, please contact Support.