Comment replies are not being sent

If your comment-triggered flow runs but the private DM or the public reply never arrives, check Meta's comment rules, the per-run limits and the content restrictions.

Last updated: September 30, 2026

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Check the private reply rules
See what was dropped from the content
Public reply problems
Comment moderation (hide, unhide, delete) problems
Confirm the trigger actually matched
Other known issues and limits

You built a flow so that anyone commenting "price" on a post gets an automatic DM. The run appears in the logs, the flow runs, and yet the person received neither a DM nor a reply under their comment. Comments follow special rules on Instagram: one reply per comment, inside a limited window, and plain text only. This guide helps you work out which rule you hit.

⚠️ Note: The comment rules are Meta's and apply to every tool using their API. WhatsApp has no comments, so this guide is for Instagram accounts only.

You may be seeing one of these situations:

The private DM never arrived.
No public reply was written under the comment.
The message arrived but the buttons and the image were dropped.
A hide or delete comment step did nothing.

A concrete example: a cosmetics brand sets up an automatic DM for anyone commenting "price" on a campaign post. It works perfectly on day one, and on day two some people get nothing. The logs show every one of them had commented for a second time: the comment had already been answered once, and Meta does not allow a second private reply. The fix is a branch in the flow that handles the "already answered" case.

Check the private reply rules

A DM sent from a comment is called a private reply, and it has three strict rules.

Once per comment. A second private reply cannot be sent to the same comment. If the flow runs again, no DM goes out.
Within 7 days of the comment. After that, a private reply cannot be sent.
On live video comments, only while the broadcast is running. Once the broadcast ends, no reply goes out.

In the log these appear as:

A note that a private reply could not be sent because it is allowed once per comment and within 7 days of it.
A note that the live broadcast may have ended, because private replies to comments only work while it is running.

If the person had already messaged you and the 24-hour window is open, the message goes out as a normal DM and these rules do not apply.

See what was dropped from the content

A private reply carries plain text only. Anything else in the message step is dropped.

Open the run log.
Look for the note under the send line saying it went out as a private reply under the comment, plain text only.
Read the "not delivered" line to see what was dropped: buttons, cards, list rows or file.
Fix the flow: make the first message plain text. When the person replies, the window opens and you can send buttons, cards and files in a second message.

Public reply problems

Writing a reply that everyone can see is a separate step with its own limits.

At most three replies per run can be written under a comment. Once the limit is reached the step is skipped and the flow continues; the log says the comment reply limit was reached in this session.
Without comment context the step is skipped. If the flow started from a message, there is no comment; the log says there is no comment context.
"The comment reply could not be written." Meta refused the request; the comment may have been deleted.
"Comment not found (it may have been deleted)." The person deleted their comment.
Public reply text has a length limit too; long text is shortened.

Comment moderation (hide, unhide, delete) problems

At most two moderations per run. Once the limit is reached the step is skipped; the log says the comment moderation limit was reached in this session. This counter survives a wait step.
"Comment moderation is not available on this channel." Your connection route may not support it.
"Comment deletion not confirmed: the step did not run." Deleting is irreversible, so the step does nothing until you tick the confirmation box.
"The comment could not be moderated." Meta refused the request.

Confirm the trigger actually matched

If there is no run in the log at all, the problem is the trigger, not the reply.

Open the automation and tap the start node.
Confirm the trigger type is Post comment.
Is a specific post selected, or all posts? With the wrong post selected, it never fires.
Check the source (posts only / live videos only) matches reality.
Look at the replies to comments box: comments under your own reply do not trigger by default.
If a word from the comment is in the excluded words list, the trigger never fires.
See my automation never starts for more.

Other known issues and limits

A comment does not open a conversation in the inbox. A thread only starts when a private reply is sent; see someone is messaging but the conversation does not open.
Comments from your own account trigger too and the reply comes to you; keep that in mind while testing.
Replying to a post you were tagged in is not supported on every route. The log may say this channel does not allow replying to a tagged post.
On accounts with heavy comment volume, a dedicated mechanism switches itself on in the background; you do not need to do anything.
The public comment reply step depends on your plan. If you are told your plan does not cover it, the portfolio owner needs to upgrade.
Deleting a post takes the comment context with it. Turn off the flows tied to a campaign post before you remove it; otherwise runs open for nothing and the step is skipped.

If you have followed every step and the problem continues, contact our Support team.

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