unsolicited call

5 times in 3 days I received unsolicited calls on my cell phone.  The number left on my cell phone was 609 847 3029.  I called back to find out who was trying to reach me.  Finally I spoke to representative named Rodney who was very difficult to understand.  He said he worked for a company called Visa and Master in Fort Lauderdale, Florida.  They were trying to offer me reduced rates on credit cards.  I asked to speak to a manager to find out why they were breaking the law by contacting me but none was available.  Rodney said he would add me to their do not call list.