I used it the other day and the boarding passes seemed messed up but I saved it to pass book so was able to use it ok thankfully. I thought it was just me doing something wrong.
I tried it yesterday and it worked fine for my flight, however I had to log on to main website to add my plus card number to get the seat selection for free. But the actual boarding pass worked fine. I was using the iPhone device - not sure if it makes a difference.
I hopes you manage to get sorted soon. If all else fails, manually printed cards are available at check in free of charge.
In the meantime try that email address or social meedja if reinstalling doesn't work.