What service to use to check telephony?

Question

Telephony

Good afternoon!
The point is this. There is a specific number.
I would like the service to call this number, play an audio message, for example, "If you hear this message, press 5". The subscriber presses 5 and the handset hangs up. Successful and unsuccessful calls are marked in the statistics. In case of an unsuccessful call, an email is sent to the post office.
Calls are made at a certain time, several times a day. Round-the-clock access to the statistics of successful and unsuccessful calls.
Interested in the service, that would not depend on one service provider. Pay for the service n-th figure for a certain number of calls, etc.
The possibility of answering the call is checked rather.
Under the number is a PBX with call forwarding to 2 SIP phones and 2 mobile phones. phone. The main thing is that someone, no matter which of these four subscribers picked up the phone and pressed the number.
Busy. The likelihood of this exists, but is extremely small. Ideally, the following algorithm in this case:
Call to the number - answer Busy - registration Busy in statistics - call again after 1 minute, etc.

Answer 1

Haven't heard of this.
If you want to measure only hits and misses (answered or not), then sipp or StarTrinity might work . Processing and notification scripts will have to be written by hand.

Answer 2

So telephony is checked, or the presence of a person near the phone?
And if it's busy - an unsuccessful call?

Answer 3

hlr - request , no ?

Answer 4

All this is done through a call center. find and negotiate. there is even a function to create an electronic report and send it to the customer))) everything is fully automatic.