To ensure you're able to build the App for your Device please create a fastlane/devices.txt and add your device's UDID.
You may use fastlane/devices.text.example as a starting point. Please note that fastlane expects you to use tabs in this file.
After adding your device please run bundle exec fastlane ios register_devices to add your device(s) to the Apple Develper Account.
Then run bundle exec fastlane ios update_certificates to re-generate the Codesigning Provisioning Profiles.
You should now be able to run the App using Xcode on your Device.
To run the App on your Device you'll need to take care of Codesigning yourself by adjusting the App's Codesigning Settings in Xcode to your needs.
We're using Fastlane to deploy the App to App Store Connect. Please see the Fastlane README on the available commands.