Unauthorized API calls

[DaSpors]

We use the sipgate REST API to setup sipgate.io URLs for our application as documented here:
https://api.sipgate.com/v2/doc#/settings/setSipgateIoUrls

Everythig is fine until the customer deletes his account on our side. We then drop all customer-related data but are still receiving calls from the sipgate.io system. Those calls are token-secured but the tokens do not exist anymore. The API-Calls are unauthenticated and we send a "403 Forbidden" header back, but this does not stop sipgate.io from polling on and on.

So feature request: React on some HTTP headers by stopping or allow an XML response to the "newCall" event that will make sipgate.io remove the URLs and stops calling our API.

Sample 1: Stop and remove config on sipgate.io side)

<?xml version="1.0" encoding="UTF-8"?>
<Response>
    <Unauthorized action="stop"/>
</Response>

Sample 2: Pause for some minutes/hours/days/calls

<?xml version="1.0" encoding="UTF-8"?>
<Response>
    <Unauthorized action="pause" value="1" unit="minute|hour|day|calls|..."/>
</Response>