Originally Posted by
Ronburggundy
What is normally happening in these situation is there are two or more addons trying to simultaneously trying to auto accept the group invitation.
oQueue by default will auto accept oQueue group invites, but if you are running a addon like ElvUI (sp?), which also is set to auto accept group invitations, one of the addon will accept the invite, and then the second addon tries to accept the invite, but because you are already in the group, it actually kicks you out of the group.
We usually suggest you disabled the feature withen ElvUI, but disabling it in oQueue works just the same.