Comment-to-DM Instagram

Follower versus non-follower is the tell, and it usually isn't the trigger. Instagram routes a DM from an account you don't follow into Message Requests, and anything that looks automated tends to get pushed further into the hidden spam section inside requests, where there's no notification at all. Long-time followers get it in their normal inbox, which is exactly the split you're describing.

Two things worth doing before you pay for anything:

1. Test with an account that doesn't follow you and actually dig for it. Inbox, then Requests, then look for the hidden or spam section inside requests, not just the top of the requests list. Most people check the main inbox, see nothing, and conclude it never sent.
2. Have that same test account follow you, then comment the keyword again. If it arrives that time, the automation is firing fine and you're looking at message placement, not a trigger problem.

If it does turn out to be placement, the things that help are keeping the first message short and conversational with the link in a second message after they reply, and varying the wording rather than sending one identical DM to everyone. It's a Meta filtering behaviour, so it happens on any tool, and it's improvable rather than fully fixable.

Ok, gotcha! On the DM, it starts with a prompt and not a link to try to avoid the spam issue. Also the automated comments only work for long time followers. Some of the people followed me, and then commented I believe, so it is not working for brand new followers either. 

On my end, I am seeing that no message nor comment is sent out to those people.

Will definitely try tip 1. 

Hi ​@ZMedia, if the public comment reply isn't going out either, I don't think this is a Message Requests issue. Requests would only affect where the DM lands, not the public reply. It looks more like those comments aren't reaching the automation at all.

Since it works for long-time followers but not for non-followers or people who just followed you, I'd check Instagram's Limits setting: Settings and privacy → How others can interact with you → Limits. That feature hides comments and DM requests from accounts that don't follow you or followed you recently, which is exactly the group that's not getting a response. I can't confirm that's the cause, but if it's on, turn it off and test again with an account that doesn't follow you.

And to your question, yes, Comment to DM is meant to work for anyone who comments, followers or not, so this isn't how it should behave.

Thank you ​@cata_rendon. So I can still see their comments, it isn’t hiding them completely. But their comments aren’t triggering the automation. I did check the “How others can interact with you” and it says it is turned off. So it seems there is some issue with the comments not triggering although I can still see their interactions with my posts. 

Thanks ​@ZMedia  for checking, so Limits is ruled out.

If you can see the comments but nothing goes out, not even the public reply, it looks like those comments aren't reaching ManyChat. One quick way to confirm: go to Contacts in ManyChat and search for one of the new people who commented. If they're not there at all, ManyChat never received that comment.

At that point there isn't much more you can change on your side, it's something Support needs to check on the account. You can try opening a ticket directly here:
https://help.manychat.com/hc/en-us/requests/new?ticket_form_id=11756694468892

Include the post link, the username of a person who commented, and the time they commented. That makes it much faster for them to look into.

About the welcome message working only once, there's a known issue with Follow to DM right now: https://status.manychat.com/

​@cata_rendon ok, thank you so much. So yes, the commenters are in fact in my contacts. So it looks like ManyChat is receiving the comments. For some reason, it is not triggering the reply to comment automation or the initial dm (there is no link in the first dm automation to avoid being registered as a scam). 

Thanks ​@ZMedia, that's a useful clue. One thing I'd check before assuming it: open one of those contacts and look at when they were added and their last interaction. If it matches the time they commented, ManyChat did get the comment and the automation just didn't fire. If it's from before (a follow or a DM, for example), the comment might still not be reaching ManyChat.

Either way, with everything you've already ruled out, this is something Support needs to look at on their side. If you haven't opened the ticket yet, you can do it here:
https://help.manychat.com/hc/en-us/requests/new?ticket_form_id=11756694468892

Add the post link, one of those usernames, the time they commented and what you saw in their contact profile. That gives them exactly where to look.

Ok, thank you so much ​@cata_rendon for giving your time to try to help sort it out. I will open a new ticket with ManyChat.

Good! I am glad it helped.