CF Tunnel is freezing my router!?

Hi, I have started using Cloudflare Tunnel to connect to my home network but after the tunnel was up (with the docker container) my router has started to freeze frequently (about every 12-24h after every reboot). The router hangs completely and is unresponsable. Only turning off and on again helps.
Since I have stopped the docker container and the tunnel is down, the router works normal again without freezing for more than 48 h.
The router is a Cisco RV325. I had set up only 1 tunnel with 1 wildcard host name.
What could be the issue?

Thanks for any hints.