Facebook Comment Auto Reply: Comment-to-DM for Page Posts

What does Facebook comment auto-reply do?

“+1”, “how much?” and “want” pile up under a Page post while you're away from the keyboard. By the time you answer one by one the next day, the moment has passed.

With an “FB Page post comments” activity in Social Automation, every comment under the post that matches your keywords gets two automatic responses, often called comment-to-DM:

• A public reply under the comment, such as “Just sent you a DM, check Messenger!”, so other readers see the comment was picked up. Write several versions and the system rotates them.
• A Messenger DM to the commenter with the product link, promo code or ordering steps, as text with link buttons or as a card carousel.

Every trigger, successful or failed, is logged in Trigger Logs with the reason for any failure. Social Automation runs on Meta's official APIs (its Facebook and Instagram permissions passed Meta App Review); it isn't a scraper or a browser extension.

How to set it up: an “FB Page post comments” activity in 5 steps

The only prerequisite is permission to manage the Facebook Page. When you sign in with Facebook, tick that Page on the permission screen. Then:

1. Connect the Page on the Connections page with one-click Facebook authorization.
2. Create an activity with “FB Page post comments” as the trigger, or start from the “FB Page comment auto-reply” quick-start template and edit it.
3. Choose which posts it applies to: all posts, pick from the list, paste post links or IDs (comma-separated), or “apply to the next post automatically”. Set it up before you publish and the next post is covered from its first comment.
4. Add keywords and pick a match type: comma-separated, such as `+1, want, deal`; leave it empty and every comment triggers. “Contains keyword” fires when the keyword appears anywhere in the comment; “Exact match” needs the whole comment to equal it.
5. Write the public replies, build the DM, and set the activity period: always active, or scheduled with a start and end time. Publish, and it runs.

What can the Messenger DM contain?

The DM is where people go to buy. You build it in the block editor from three block types:

• Text + link buttons: up to 3 link buttons, each with its own title and URL. Good for one product, or a promo code plus an order link.
• Image: upload a file or paste a direct image URL (jpg or png, up to 8MB).
• Card carousel: up to 10 cards, each with a title and subtitle (up to 80 characters each) and up to 3 buttons. One card per product when a post sells several.

Only one DM is sent per trigger

Each trigger sends a single DM, and blocks follow this priority: any cards, and the whole DM goes out as a card carousel with text, buttons and images left out; no cards but an image, and only the image is sent; text and buttons only, and it goes out as text with buttons.

Ask one more thing after the DM: subscribe to updates?

A Facebook Page comment activity can add a “subscribe” button after the DM; people who tap it join your subscriber list. Meta allows asking each person at most once a week. Broadcasts and drip sequences to that list (Messenger marketing messages) are pending Meta's permission review; once available, Meta bills each delivered message to the business's own ad account.

Timing and rules: 7 days, once per comment, which activity handles it

• Within 7 days: the Messenger DM is a Meta Private Reply and must be sent within 7 days of the comment. The activity has to stay “active” to reply in real time.
• Once per comment: put the link, code and instructions in one DM rather than several.
• One activity per comment: when several activities on the same Page match, an activity limited to specific posts wins over an “all posts” activity; within the same level, the activity created later handles it.
• Comments during a live: while a live is running, “all posts” activities and “FB Live comments” activities are ranked together, and the one created later takes the comment. Live and replay rules are in Facebook Live comment auto-reply.

Troubleshooting: public replies limited, or DMs not arriving?

Meta temporarily limits public replies

Posting the same reply many times can lead Meta to temporarily limit the Page's commenting; DMs aren't affected. Fix: write 3–5 different public replies so the system rotates them, and keep links in the DM only. The limit usually lifts on its own within hours to days.

Another chat tool is connected to the Page and DMs don't arrive

In Meta Business Suite go to Settings → Integrations → Conversation routing. Set the default app to Crescendo Lab or leave it unset (not another tool or Page Inbox), and under Crescendo Lab's Manage turn on Take control of conversations and Access all conversations; do this once for Messenger and once for Instagram. When the default app is another tool, that tool takes the regular DMs.

Trigger Logs show a failure

Read the reason in the log. The usual ones: the comment is older than 7 days, the activity isn't “active”, or this comment already received its one DM.

Templates you can apply, and what it costs

Quick-start templates for Page comments include “FB Page comment auto-reply”, “Comment +1 to get a promo code”, “Comment ‘want’ to get the freebie” and “FAQ auto-reply (shipping, dispatch, returns)”. Apply one, change the keywords and DM, and publish.

Plans are priced by connected accounts and activities: Lite US$29/month (2 accounts, 5 activities), Standard US$79/month (5 accounts, unlimited activities), Pro US$129/month (unlimited accounts and activities); paid plans have no trigger cap. Every plan starts with a 7-day free trial. See pricing.

Running the same campaign on Instagram too? Create a second activity for Instagram; see Instagram comment-to-DM setup.