New service order = severe migraine!

My parents are 85 years old, so I have been assisting them with connecting new service to their new home.  Have gotten the run around from Xfinity Customer Service (joke, more like lack of....) for the last 4 weeks.  Need an underground crew and a construction crew and a technician but only a technician has shown up (twice now) and says cannot do anything until underground cable is installed.  That was suppose to of happened two weeks ago.  I don't understand the lack of quality service, this should be a very simple process.  Please help!!!!!!!!  Parents are old and require internet (for grocery shopping) and landline phone (for contacts)