"Social Auto-Replies" is Working for DMs But Not for Comments

This feature is in “beta” and Klaviyo admits there may be bugs...but this would be a pretty big bug. 

I set up the “social auto-replies" Instagram integration and set the trigger word to be "launch" (with and without quotes).  

The automation trigger is working if someone sends a DM (direct message) with the trigger word, but it is NOT working if they comment with the trigger word (which is the method I would prefer to use).

I have confirmed that everything is (or seems to be) configured correctly according to the Klaviyo help doc ( https://help.klaviyo.com/hc/en-us/articles/41741460845339 )  including…

1. Both 'comments' and 'dm' are selected as the listening triggers
2. the Instagram account is a business account;
3. the post in question is not a collab post;
4. the keyword 'launch' is not being used elsewhere in the account;
5. I tested it with 4 *public* Instagram accounts (it won’t work with private IG accounts)

Has anyone been able to get this to work when someone COMMENTS the trigger word? 

Thanks in advance for any help / advice!