Cannot connect with controllable Zwift

Hello. I have a Tacx Flux and a android phone (S7) with Companion installed.
I’ve had the same intermittent problem : Controllable pairing only happened once in a while. So I found a protocol that succeeds every time, here it is (after 2 months of testing) :

  1. Make sure the Tacx trainer is unplugged, and bluetooth is only enabled on your computer (not on the phone). The Tacx Trainer must be close (within 3 meters) to the computer.
  2. Restart your phone
  3. Start the Companion app on the phone
  4. Start Zwift on the computer
  5. Once the pairing window appears, turn on the Tacx
  6. The three active connections should appear