When Google launched Android 8.1, they made a change that affected our products when pairing: They made it so in order for an app to access the name of the WiFi network you're connected to, you have to allow Location Permissions.
As a result, if you don't allow the app to access "Your Location", you will be unable to pair. Rest assured that this permission is ONLY used to access the name of your WiFi network for ease of pairing, and we're not actually tracking your location (we're seriously not interested, nor are we interested in sharing it with anyone).
So if you've already said "No" to giving the FS Home app permission to access your location (and you can take it back after you're done pairing, that's the ONLY time it's needed) you just need to navigate through the settings on your mobile, in the mobile OS (not the FS Home app):
Settings > Apps & Notifications > App Permissions > Your Location
Then just scroll down until you find the FS Home app, and enable it (or you can disable it if you want, after you've paired your products).