Text notification for inactive participant

I have a question related to sending out sms/text notification about new conversation message to non-sms conversation participant. I am using webhook to check for new messages in conversation.

Consider JOHN and MIKE are two non-sms chat participants and I have text numbers too for both participants.

If JOHN and MIKE (both non-sms chat participants) leaves the conversation, and MIKE sends a message in conversation after couple hours, then how can I decide that now is the time to send out the sms/text notification to JOHN for new message in the conversation.

In short what is the best practice to send out sms/text notification to non-sms chat participants to notify about new messages in conversation?

Answers

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