If a customer DMs your business on Instagram or Messenger and you answer through a tool that uses Meta’s API, you usually have 24 hours to reply. After that the conversation’s messaging window closes, and the tool cannot send a normal reply until the customer writes again. Comments work differently: there is no 24-hour window for replying to a comment, but an unanswered question under a post stays in public view, where other potential buyers can see it.
The 24-hour messaging window
Meta calls it the standard messaging window. From its messaging policy overview:
- The customer opens it. The window starts with a customer action, such as sending you a message.
- It usually lasts 24 hours. For most customer actions, the window is 24 hours long.
- Ads can extend it. When someone sends their first message after tapping a Click-to-Messenger or Click-to-Direct ad, the window can last up to 7 days from that message.
- Speed is encouraged. Meta’s own wording: “Responding to people’s messages as soon as possible is highly encouraged.”
Each new message from the customer opens a new window, so a conversation that keeps going stays open. The limit bites when a message sits unanswered for more than a day.
This applies to replies sent through Meta’s API, which is how business inbox and automation tools work, VivaDialog included. When you try to answer a DM in VivaDialog after the window has closed, the reply is refused with a note that the customer has to message first.
Comments are different
Replying to a comment is a public reply on your post, not a message, so the messaging window does not apply to it. You can answer an older comment whenever you get to it.
Two things still argue for answering comments quickly:
- Everyone can see the question. A comment asking for a price or a delivery date stays under the post. People who scroll past later see whether you answered.
- The DM option expires. Meta lets you send one private DM to someone who commented, but only within 7 days of the comment. See how to send an automatic DM when someone comments.
VivaDialog’s automatic rules also have a limit of their own: they never answer anything older than 24 hours. That is our choice, so a rule does not suddenly reply to a backlog of old comments. You can still answer old comments by hand from the inbox.
How to keep up without living in the app
Most accounts that fall behind get the same few questions over and over. A setup that keeps the window open:
- Put comments and DMs in one inbox. Checking Facebook, Instagram, and Threads separately is how messages get missed. VivaDialog shows all three in one list.
- Answer repeat questions with rules. Price, location, opening hours, and “is this still available” can be answered by a keyword rule with a fixed text or an AI reply that uses the facts you give it. How to auto-reply to Instagram comments shows the setup.
- Acknowledge DMs right away. The “DM away message” template sends every new DM a short note that you will reply soon, with a reply time you choose. Only promise a time you can keep.
- Tag and assign what needs a person. A rule, or you by hand, can tag a conversation, for example
lead, or assign it to a team member. In the inbox, the Nobody handling yet view shows what no one has picked up, and team notes keep context such as “asked for the wholesale price” that only your team sees. - Check the inbox at least once a day. That alone keeps most DMs inside the 24-hour window. For a customer who asked and then went quiet, a rule can send one reminder within the window; it is cancelled if they write back first.
When the window has already closed
Apart from a few message types Meta allows for specific cases, a tool cannot restart a closed conversation through the API; the customer has to write first. Answer their comment publicly if there is one, and make the next post or story easy to respond to. When they message again, a new window opens and you can reply as usual.