If a person has left the group in the past, you need to be in their Telegram contacts to add them back.
They can still join via an invite link as long as they are not on the group's invite link as long as they are not on the Removed Users list.
194
抱歉，若用户退出了群聊，您需要他们添加的双向 Telegram 联系人中才能将他们添加回来。
备注：如果他们不在被移除的用户名单中，他们可以通过邀请链接重新加入。
82/194
Robert Lyu,
Dec 24, 2021 at 02:18
抱歉，若用户退出了群聊，您需要他们添加的双向的 Telegram 联系人中才能将他们添加回来。
备注：如果他们不在被移除的用户名单中，他们可以通过邀请链接重新加入。
77/194
Robert Lyu,
May 25, 2020 at 03:58