I noticed a little water in the bottom but didn't think anything about it. I ran a load of dishes and at the end of the cycle about an inch of water remains. The model is FDBB2040FC1 and the serial # is TH73187120. I have ran the disposal to see if it is clogged. Nothing. The sink drains fine as well. I see a piece of plastic that looks like a drain cover in the bottom wtih a "handle". However, it doesn't lift up. Any suggestions?