Got a voice mail - recorded message stating "Please call Mr. Michael today...very important that you return this call today..." Tried to call back - just get a recorded message stating the number is not in service...but still get daily calls from this number...
If it is a collection agency, never a good idea to avoid the calls. If you owe a debt, work it out. If this is not you, let them know and the calls will stop. It's all very simpl.