Can't join a team

[Jean-Parpaing]

Hello, I have been added in the team "Stairway to VF", it's written on my profil page, but I'm not in the member list on the team page. I can't add or update any chapter with the team name. Additionally, the leader can't add me again because it says that i'm already in the team, but I can't leave it.
What can I do ?