there are two types of short codes :
On Demand Shortcodes
This type of code is used when you need to reply to clients one time. A client sends a message and receives a reply and that's it. Hence the name On Demand(i.e send messages On Demand)
As the name suggests the client only sends a message once and they get subscribed to your service. i.e they receive messages from your code daily or weekly or as you specify.
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