Shop creates a Scheduled App Post with Post to Instagram checked on it, the schedule post gets posted to App and FB at the scheduled time, however, no post is actually getting created for Instagram.

Somewhere during the time when the posts get sent to App & FB, it does not send it to IG, that looks something is broken there. Apart from that Immediate App Posts and Direct Posts to Instagram works fine. If shop schedules or sends immediately the direct Instagram posts, it works fine.

This is a known issue, we are unable to schedule to IG at this time, the interface is definitely confusing, when scheduling and FB Post.