I'm happy to misspell their name.
my house phone clearly states on the voicemail that I will not listen to the messages, and it's best to call me or husband on our cell-phone.
My cell provider sends me my voicemail into my email inbox, so I don't have to waste the time retrieving the message. I think the outgoing message says to contact me by whatsapp or email.
That's what I did. The only downside is that if you don't pick up a call you have to listen to it ringing for a bit longer.
If you remove the voicemail then you lose the outgoing message.
I suppose you could also go with the other popular copout of deliberately leaving the mailbox full.
I just received a message from them saying "Congratulate <name withheld> for starting a new position as Storage Professional at Open to opportunities"
How do you even answer that? "Oh hi! Congratulations on your unemployment!"
That is all.
And I still think that both Spark and Teams are nothing more than dressed-up but inferior clones of IRC.