Forget your objective of booking a meeting.
Forget them having to say YES.
Just have this one objective in mind: -
*Focus on connecting with another human being and making them smile*
...then listen as their barriers go down.
...and they pay you the compliment of listening to what you have to say for at least 30 seconds.
Laugh at yourself.
Joke about the call ambush.
People really don't mind.