Sip registration script

I am looking for someone to write a script for me that will do the following:

Check my sip clients for registration every 5 minutes and email me if not registered.

For example:

John has 3 phones in his office in which I host on freepbx. Ext 100, 101 and 102

Ext 100 was unplugged by accident. I would like to be notified via email of this

Ext 101 can not be reached the next day because his internet went down.

I would like to be notified of this via email.

I also need an easy way to add and delete new clients from time to time.

I am currently running FreePBX 12 .

If you can help me please let me know.

By the way - I am willing to pay !

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