Forcing callers to press "1" in order to leave a voicemail

Currently callers are not required to press a button to leave a voicemail (i.e. press “1” to leave a voicemail) which allows lots of robo messages to be left on our voicemail box.

Is there a way to require callers, once they are already into the extension’s unavailable voicemail box, to press “1” in order to leave a message and if they fail to press “1” the system doesn’t record a voicemail?

I had the same problem and the only way I was able to accomplish it was by using a voicemail blasting instead of the user specific mailbox. Either if you use a system recording or the default “Read group number” as Audio Label, the system will by default ask you for a confirmation (“If this is correct, press 1”). If there is no action from the caller, the system will automatically disconnect the call after a 20 seconds timeout.

I hope this helps!