Can't be added to a group

[PnJJ]

Recently I joined a group who translates manga n stuff and they said to me to join MangaDex group too. Two days ago, I sign up an account to this site and my friend send me invitation, I accept it and nothing happened. I did a research a little bit and found out it has to past 24 hours before making an action. I start waiting and waiting. And then 24 hours past and my friend trying to send me link but I can't see in the group profile. Please help me
Groups name: NeyZen Manga