Who called from 7864721775

Phone rang three times. Did not recognize. Did not answer. No message. Blocked.

How did you block them?

Work number, someone calls lots of people talking in the back.  Guy says Hello, I say can I help you, he hangs up. Showing from Miami, FL

I keep getting several calls a day like the one I just got from this number asking me if I take prescriptions. How do I stop it. It usually is always a different number

I didn't answer the call since I didn't recognize the number.  There was a voice mail message from this number but it was just heavy breathing and the background sound of chitter chatter of a call center.  So,  will have to guess this was some scum bag telemarketer