We have a process with 3 users involved. The process posts an event in news

We have a process with 3 users involved.
The process posts an event in news using the Post Event Smart Service, putting the 3 users as viewers. The 3 users participate in a discussion, when necessary, they want to invite other users, but the "Add Participants" button has become a padlock and they are not allowed to invite other users.
Any ideas?...

OriginalPostID-116839

OriginalPostID-116839

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