I was a Garmin user (Forerunner 935) until now, I bought Polar Vantage V. When I used Garmin Forerunner 935 with TrainerRoad on my iPhone and SmartTrainer (Wahoo Kickr) for training I was able to connect with both at the same time showing all metrics. However with Polar Vantage V I’m not able to do the same connection.
It appears that the Polar Vantage V offers BLE communication only. This matters because BLE is a one to one connection between devices.
If you have an older Kickr (not the most recent 2018, 2020 or Core models), you have only one BLE connection on the trainer. This means the connection between your iPhone and Kickr use the only BLE connection that you have, and that means you won’t be able to connect to the Polar.
If you have one of the most recent 2018, 2020 or Core models, make sure you are on the latest firmware. These models each offer 3 total BLE connections, and can do what you want.
Essentially, you are running into a hardware communication channel issue, not TrainerRoad issue. Your old setup worked because the Garmin picked up on the ANT+ signal from the trainer, but your new Polar does not have that option.
Thanks very clear your answer!
If there is some else with the same problem, I found this gadget which converts Ant+ protocol to Bluetooth.