Simple.
At the bottom of the rails that it slides on there are 2 adjusters. One each side.
So on the inside face of the door near the bottom with the door card off.
There are 2 nuts and a torx shape bolt inside the nut.
Loosen the nut and adjust the torx to bring the bottom of the window out, so toward the metalwork of the outside of the door.
The top.will pull in and glass will pop under the lip.
You may need to remove battery lead for a short while and then connect to recalibrate the window. The window will drop as you reconnect the battery.
Then simply hold switch till it meets the top.
Job done !!