The one ring is intentional.

Then when you call back and get a busy signal, that is called a trap line. It traps and saves all you information such as name and telephone number.

The promise of a Rx card is just a lie to get you to call back so they can trap your information.

It is an old collectors trick, but people still fall for it.

You also need to know to never call back on an 800 or other toll free number even if you think your caller ID is blocked. It is NEVER blocked when you call a toll free number because the person paying the bill has a right to know who is calling on their toll free number.

If you want to call and bi*** out a collector, do it from a number that cannot be tracked back to your name, ie WalMart throw-away phone. Otherwise, you will start getting calls by the hundreds.

Rings one time hangs up.

When I try to call back all I get is a busy signal

Rings one time.

When I called back, it promised a prescription card, if I gave it my name and address.  The recording started a couple of seconds after the start of the message, so I missed name of the called - probably deliberate.