Their office of Central Reservations calls and sells timeshares for GEVC as well as for other firms such as Great Destinations. They are notorious telemarketers.
I found the "missed call" on my cell phone. They left no message. I called the number back from a land line and got a live person. Despite the Dallas area code, they are probably in India or a call center in Southeast Asia. They are peddlers claiming to represent Global Destination something or other. I told her they called my cell phone and I need that number taken off their call list. She said, "Okay, maam." I started to tell her that they can get in trouble and she said, "Okay, okay, okay." And hung up.