Worst Customer Experience

My family has been using Dell for years, but this will likely be the last one we ever get if we even get this one.  I placed my order through the Dell website, but the order did not process due to Dell having the wrong billing address despite all of the correct information being put in at the time of placing the order.  A sale rep. did call to inform me of the issue, but they messed up my order by forgetting my promotional code when they resubmitted the order.  So now I've been dealing with the online chat and phone system.  After almost 8 hrs of dealing with these systems I still can't get this issue resolved.  Phone system is garbage.  System just hangs up randomly or they transfer you to someone just to transferred again.  I've been waiting on two call backs since last week and still haven't heard anything.  It shocks me how much issue they are giving me with fixing a $150 promotional deal on a $6000 order, but if they would have resubmitted the order just like it was originally when I placed it there would not be an issue.  I am getting to the point of just wanting the cancel everything because I don't feel like I can trust the company to support the product which I am purchasing.