Hi @Lilja 

By sync I assume you mean group. To group a Sonos to another Sonos go to

System > Select the Sonos speaker that is Active (playing) > Tap the Square with the Up Arrow (in the upper right corner of the active speaker) > Select your other speaker(s) > Click Done.

Your Move must be in Wi-Fi mode and connected to your network. Let us know how things sort out.

Cheers!

Mod Edit: edited for clarity prior to marking as Best Answer

Are you trying to create a stereo pair or group them together - these are two different things? To create a stereo pair, you need to have two identical devices. To group them together, please select the play controls for the music playing and then select the small up arrow in a box to the right of the screen. You then have the option to select both your Move and your Sonos One - this will then output the same audio to both devices.

Thank you very much @AjTrek1 and @UKMedia .

You were right, I meant grouping them together and thanks to you I now have and am very happy :)

Have a great day!