Cannot find or join my friend's LAN server

I have tried many times and did a lot of research about playing in a LAN server. 

These are some background:

1. My friend and I are on the same wifi so our network should be fine to play LAN game.

2. Both my friend and I were playing DST in offline mode, and the server was created in LAN mode of course.

3. I have switched the LAN tag to yes, but I still cannot find any LAN server.

There seems to be no problem at all but I just cannot find the server in the browser and although I can see my friend status "playing Don't starve together" there is no "join" tag under my friend's right click menu.

Please help

Thanks