I have a Holmes HAP726 air purifier. I just replaced the carbon and hepa filters inside of it. Now, I can't get the cover back on. There is this weird plastic thing on the left hand side of it. In the instructions, which are very weak, it says... "Replace front grill by aligning tab on left hand side and swinging down. Gently press until the front grill is firmly in place." I don't know if the weird plastic thing is the tab? It doesn't seem to fit anywhere. I am very frustrated with this and don't want to take it to the garbage can. I have been through so many hepa filters. They all seem to break or having something wrong with them when it comes time for filter replacement.

Air Purifiers - Holmes Products - HAP726-U Air Purifier