Can't connect to a 800 number
 

Long time lurker, first time poster. Using a VZW 9530 and I cannot connect to a particular 1-800 number I need to call often for work. I started a trouble ticket with tier two tech support about two months ago. They eventually created a "duplicate device" (a 9530 with my phone number associated with it) and made numerous calls to said number without problem. My problem persisted and eventually VZW sent me a new device. I have updated the new device to the most current OS out there, .419 I believe, still can't call this number. When I dial the number I get a long ring, maybe 1 1/2 to 2 times the normal ring duration followed by a two tone busy signal, then disconnects. It is exactly the same every time I attempt to call. I have asked the people at the number I'm trying to call and they can't find any problems on their end, said they take about 10,000 calls per week on that number. Any help would be appreciated.