If you are on the RoboTower, you can check that it's in LAND mode, using the display of the handset of the RoboDIMM
telescope. Toggle through the menu by pressing the MODE key until you see
"telescope", as follows:
|next item|| SITE
|scroll down to Align and press
|next item|| AZALT
|scroll down to see a tick against LAND.
If it's not, then select LAND using <enter>
(The MODE key is in the middle of the top row of button and the Scroll
down key is on bottom right of the keypad.)
Close the entry hatch as you leave. You can close the dome as you are
leaving the WHT in your car at the end of a normal night.