There are problems with the sense servers since it is not connected to the server, the IOS application and the web browser.
I’m trying to install a sense device and confused if I’m not installing it correctly, or if there are system issues. It would be my luck that I’d bang my head for 2 hours only to find out it wasn’t something I had done.
Just noticed it was not working on the web and checked my phone and down there too 
We’re investigating.
Please follow https://status.sense.com/ for updates.
Everything is back up and running. Thanks for reporting, guys.