Can Android TV be attached to an existing wall-mount unit (for example, a standard VESA mounting interface)?
If the wall mounting fixture that you are using is Sony made, you may be able to attach the TV.
Check the manual included with your TV to see if the mounting fixture is a compatible separately sold accessory.
Because it is necessary to attach extra parts to the backs of some TV models before mounting, be sure to check the instruction manual that was provided with your TV.