← Channel guides
Messaging policy
How long you can reply, per channel
Most messaging platforms limit how long a clinic can freely reply, counted from the last message the patient sent. Once that window closes, you cannot message first with a normal text — you need a pre-approved template, or the patient has to message you again. The window differs by channel, so here is the full picture.
Every new message from the patient resets this clock to the start. During an active back-and-forth you rarely notice the limit — it only matters when you go quiet and try to reach out later.
ChannelReply windowAfter it closes
💬LINE
No limit
You can reach out anytime. Only the free-tier send volume applies.
✈️Telegram
No limit
You can reply anytime — but you can only message a patient who started the bot first.
💬Facebook Messenger
24 hours
You can keep replying for up to 7 days via the "human agent" tag (permission required). After that, the patient must message again.
📸Instagram DM
24 hours
Same as Messenger — up to 7 days, after which a new message from the patient is needed.
🟢WhatsApp Business
24 hours
You can only reach out first with a pre-approved template. Replying within 24h to a chat the patient started is free; only clinic-initiated templates are billed.
💛KakaoTalk
24 hours (Sangdamtalk)
Reach out with a pre-approved AlimTalk template, or FriendTalk for patients who added your channel.
🇨🇳WeChat OA
48 hours (2 days)
Reaching out first is effectively not possible — only notification-style template messages from a verified account. The norm is to wrap up the conversation within 48 hours.
🇻🇳Zalo OA
7 days
A free OA can only receive; sending replies requires a paid OA package. After the window, reach out with a ZNS template.
🎵TikTok
No time limit
TikTok DM revolves around ad-initiated conversations. It is shaped by ad and account policy rather than a time window.
What the inbox shows when the window closes
When little time is left, the CRM inbox shows a "reply window remaining" banner at the top; once it closes, it turns red with "Reply window expired." Messages sent in this state may be rejected by the channel policy.
Reaching out again after the window
The best approach Reply to patient messages as quickly as you can. The faster you respond, the less the time limit will get in your way.
These windows follow each platform policy, which the CRM inbox mirrors. Platform policies may change.