opJoinRoom

Silly question, but I cannot find an answer. I've got room list using getRoomList() method. Now, I want to simply join one of the rooms. I've found opJoinRoom method, but it requires gameID. However Room class object doesn't seem to have such a field:

https://doc-api.photonengine.com/en/cpp/current/html/a05398.html

Btw. joining random room works fine for me.

Best regards