Zwift won't pair with my trainer
In rare cases, Zwift does not detect a trainer during the pairing process. The first step is to make sure your trainer is active and broadcasting, and assuming that is the case, here are two possible solutions.
Bluetooth Connections
If you are using Bluetooth to pair, your trainer can only connect to one device at a time; try turning off your phone's Bluetooth and refresh the trainer search on Zwift.
Reset Files
If you're not using Bluetooth, or if the above solution did not work, remove the device files from Zwift as follows:
On the computer running Zwift, navigate to the Zwift folder (likely in your Documents folder).
In the Zwift folder, locate and delete these two files (they may be in a subfolder):
prefs.xml
knowndevices.xml
Once these are deleted, restart your computer.
After your computer restarts, log back in to Zwift (the app will likely update but may not).
Try pairing your trainer again.