Welcome to the Fitbit Community @Andrei0987.
I appreciate your participation in the Forums and sharing the difficulty you're experiencing with connecting your Fitbit Versa with your new One plus 7 pro phone. I understand that you were using your Samsung S8 previously. Thank you for your efforts to resolve the issue and doing a factory reset of your watch. I recommend confirming if you've unpaired the watch from your previous phone: open the Bluetooth settings on your Samsung S8 phone and unpair the watch from the list.
While your new phone is not supported by the Fitbit app at the moment, it doesn't mean that it won't work with the app entirely, but rather that some of its functions might work intermittently. Usually a missing requirement is the cause and I recommend confirming the steps to set up the device to your account and the troubleshooting steps: Why can't I set up my Fitbit device?
I'll be around if you need further help!
Want to discuss ways to increase your activity? Visit Get Moving in the Lifestyle Discussion Forum.
