502 gateway - your app won't work so I have to use the Chrome browser?

Hey Atlas-Accounting, 

The app offers quick access to your books, while unlocking some powerful tab management features. It's one of the most convenient ways to access QuickBooks Online, and it's our goal to make it a seamless experience. I want to make sure we get yours up and running again. I'll be happy to help you sort this out.

We experienced a brief issue with our servers some time ago, causing error 502 for many of our customers. Since the server issue has been resolved on our end, you're most likely getting it due to an issue with the app's local data. As a cloud-based software, QuickBooks Online accesses your books through the internet, but some basic information is preserved in the app's cache to help deliver lightning-fast performance. Most errors such as this one can be resolved in just a couple easy steps to clear this data:

1. Select Help in the top menu bar.
2. Choose Reset App Data.

I'm confident this will get the app back in action again, but this article includes a few additional things you can try: QuickBooks App for Windows and Mac: General support 

Let me know how this goes!