Why didn't my automation reply?

Check these in order:

• Testing with your own account? Instagram doesn't tell us about comments you make on your own posts, or send DMs from an account to itself. Test from a second Instagram account.
• Was the comment hidden? Comments Instagram files as spam or hides never reach us. New accounts that post the same keyword again and again are often filtered.
• One private reply per comment. Instagram allows exactly one private reply to each comment, within 7 days of it. The same person commenting again on a new comment gets a new one.
• After that first reply, they have to respond. Until the person replies or taps a button, Instagram won't let more messages through. Make the first message ask for a tap or a reply (the opening message with a button in the Comment to DM setup does this), and put the link or the freebie after it.
• Look at the Safety Center. Every message that wasn't sent is listed there with the reason. Instagram wouldn't deliver is about that one person, not your account.
• Only the first reply goes out, never the follow-ups? The account is linked to a Facebook Page whose inbox owns the conversations. The fix is in Instagram accounts (look for Only the first reply is getting through).
• Lots of comments at once (a viral post)? Messages past Instagram's hourly limit wait and send by themselves, so a few people may get theirs later rather than straight away.
• Reconnect needed on the account card means Instagram's access expired; nothing sends until you click Reconnect @username.