You have set a maximum height restriction on the desk. To remove it please follow the instructions below.
Setting the maximum height of the desk:
1.Use the “Up” and “Down” buttons to move the desk-top height to the desired height you wish to set as the maximum (higher than 97.5cm).
2. Press “Up” and “Down” at the same time for 5 seconds.
3. After completing step 2 the maximum height will have been set on the desk system. The desk will now be unable to be moved higher than this height
Unsetting (removing) maximum height of the desk:
1. Move the desk to the previously set maximum height setting. Press and hold the “Up” and “Down” buttons together for 5 seconds
See the full instructions here
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