Is there a handle, lever or bar to raise or lower? Try that. If not look under it for a round handle that turns. Turn it and watch to see if it raises or lowers. If it goes the wrong way, turn the handle the other way. If it doesn’t have any of those devices, it may not be adjustable.
Is there a handle, lever or bar to raise or lower? Try that. If not look under it for a round handle that turns. Turn it and watch to see if it raises or lowers. If it goes the wrong way, turn the handle the other way. If it doesn’t have any of those devices, it may not be adjustable.
As Einstein said but wait until you are sober.
If that doesn’t work trying posting your question again in "Home Maintenance and Renovations".