If your funds are not loading or you see the "Discovery error" message, there are a few steps you can take to resolve this issue.
First, try to reset Trezor Suite.
You can reset Trezor Suite in "Settings" (The gearwheel symbol in the top right part of Trezor Suite).
Navigate to the "Application" tab and select "Reset app". Then try again to update your firmware.
If that doesn't help, check to see if you have Tor enabled. If so, disable Tor and then reset the application again.
If none of these suggestions help, please try to uninstall the Trezor Suite desktop application, and then download the latest installation file from this source http://trezor.io/trezor-suite and install it again.