Facebook "Call Now" CTA not resulting in calls despite many button clicks

Hey guys,

We've been using the "Call Now" CTA for Local Awareness ads across a few campaigns this month. Despite FB recording 60+ button clicks, we've had no calls tracked through the number (third-party tracking). I know the user gets a call or cancel popup after they click the button so I assume that's where we're getting the drop off.

Has anyone seen good results out of using the "Call Now" button? I'd be keen to hear if anyone has a different experience.