Citi/ Sears website down

I have been trying to log on to CITI Sears account for over 3 weeks now.  I have call Tech.  They said use -Chrome ( it works best) I have used I/E FireFox and Chrome.  I have tried 3 different computers, two phones and a kindle.  Tech denies there is any known problem.  I have call customer service.  Told to wait three weeks and then try again.  I have spent countless hours on the phone with customer service and tech.  No one seems to care or is willing to acknowledge a problem.