I bought my 21” SP mower on 4-14-19 at Home Depot. This past week (Sept 3) I found that my mower will not engage the blades. When this first happened I was in the low position on the handle bar. I started fiddling with the handle bar and moved it to the middle position, it did not work there either, until I lifted up on the handle bar in the middle position. The blades would engage but every time I pushed down on the handle bar to turn around, the blades would stop. Once turned around and I lifted the bar, and the blades engaged. Now this week (before I could contact the Warranty Dept) I went to mow and the blades would not engage with the handle bar in the low or middle positions. I moved it to the top position and it would not engage until, just like the comment above about the middle position, if I lifted the handle bar it would engage the blades. However, same issue - every time I pushed down on the handle bar to turn around, the blades would stop. I would again turn it around and lift the bar, and the blades would engage. I just went out to check on it again (Sept 9) and now it will not engage the blades in any of the three operating positions, low, middle, high. HOWEVER, it will engage the mover blades when I move the handle bar ABOVE the high position. This is no good as you cannot use the mower in that position as the handle bar is not in a locked position. I have documented this issue via a video that I took to demonstrate the issue with my mower. My opinion is, there is a short of sorts or some connection issues between the handle bar the engagement of the mower blades. My issue is the same as mentioned in the you tube video link from Mike and Da Dude's comment from 2 days ago.