Just got new monitor S2721DGF and put it on the stand that was sent. I cannot find any way to adjust the height of the monitor. It looks like there is a linear space that should allow for adjustment up or down, but it is all the way at the top and I cannot locate anything that will safely let me lower it? I've checked all the support documentation and it talks about the ability to swivel, but not to raise/lower height. Could not find anything online or in the community. Hope someone can help. Thank you!