Customer support/ care messages consist of two types of messages, the User-Initiated Messages, and the Business-Initiated Messages. Please click here for more details.
Yes, it is possible to send a button via HSM (Highly Structured Messages/ WhatsApp Template Message) to a customer. Follow this guide to get the button message approved.
It could be not enough memory and caused the server to be temporarily down. If the server is not connected in the health check, you could restart the server (after clicking Unlock) in the Stella platform, nad the Whstapp number will be back on line ...
This is because WhatsApp uses 24 hours of incoming and outgoing messages to calculate the limit, so the number of messages that can be sent will be different for each time period. It does not reset at a certain time of the day.