Automated call that repeats that "You must call this number immediately"

I received a call from this number telling to return this cal 7pm central time.This is the second call I have received from this company,even though I have told them to take my name off this list and not to call me. I have notified AT&T and was told not to answer this call.

This is a collection agency. If they are calling you they are trying to collect a debt. In many states you can cease the calls by saying:

I am recording this call, I am aware of your claim, I am unable to make good on the debt at this time. I have your contact information, and will contact you when settling this debt is a financial reality. Until then if you continue to call you are no longer covered by debt collection law, and I will contact the local authorities and the FCC to file a harassment complaint.

They may try and interrupt you. HANG UP RIGHT AFTER SAYING THIS.

What have you just done?
The law the allows collections says they are allowed to contact you to establish the debt validity, and attempt to collect. You have told them #1 that you are RECORDING the call (even know you're not it creates a sense of accountability on their behalf), you told them you are aware of the debt (DO NOT SAY I KNOW I OWE THAT BILL) without validating that it's yours.

Finally if this doesn't work many phones offer selective call forwarding free. Try forwarding and of the numbers they call from to the rejection hotline

This is a very shady and abusive collector, very unprofessional and threatening. You will get zero respect or professionalism no matter how cooperative you are with them. Anything other than full payment or post-dated check immediately is unacceptable. They yell and even accuse you of walking away from your debt when you try to make arrangements with them. They harrass people at work. They make illegal threats to garnish your wages. Very very irrational collectors.  

Work with the original hospital you owe the debt to because there is no way you can make an arrangement with these guys and I wouldn't trust an arrangement with them anyway, they don't even have the accurate debt amount.