You can find a team via the Facebook post - just find there an ID of an already existing Team posted by other participants and ask to join it.
You want to join a team:
To join the already existing team, you need to click on the corresponding button:
Then insert the ID number of the chosen team.
Attention! Please, insert only the ID number, for example:
After sending a request, you will see the following:
That means that your request is pending, and you need to wait until the Leader accepts your request.
You are invited to a team:
If you are invited to a team, you can accept or reject the invitation like this:
Once you accept the invitation, you will be able to see the information about the team. You can leave the team at any moment by clicking on the corresponding button: