Firstly, I'd recommend making basic checks before going into anything technical. Log into a spare FB account you have lying around and check your reel through that account real incognito like, just to see if it even shows up/ loads at all. You'll have to make your next step depending on the outcome. You might've been shadowbanned or something of the like. If it does show up or load, check if there's just a delay on when views are updated (that used to be a thing), and just kinda keep eliminating possible reasons why this might be happening.
Last thing to decide doing (imo), if you are compelled to believe this is an error, is to contact IG and or FB support team about the issue however troublesome it may be.