New user - really frustrated…

Hi,

I bought two of the L40 Ultra models for my two story 3600 sq ft home. I have spent hours on the one at this point.  I’m not sure why but it doesn’t seem to have enough suction. I had problems mapping the floorplan out and decided to clear everything and start fresh. Then I watched it as it missed all sorts of dirt and crumbs. It’s a big investment to have to babysit the thing. Is the L40 Ultra just weak or is it me? Lol

Hoping to get over the hump or get better info on what else I can do or what other models are failsafe.