You are inviting people to a group that only YOU can post in, and complaining about us not posting…
Learn to setup a group first, then make threats.
You need a bot-group or turn us all into admins, so we can post. Bots work by posting to YOUR account, as a reply from us. Then YOU add our images to the GROUP. Otherwise you have to make us all admins of the group, so we can post and remove posts. That is kind-of the point of the program.
P.S. Friends have to be "mutual", to chat, unless they are old and confirmed as not a bot. EG, without knowing YOUR name, and NUMBER, the program will not let us add you as a contact to chat with you.