Than you all for the suggestions. I opened the cap to take a look and actually found the problem. A tiny spring tensioning a lever that drops down onto the pawls broke and a small piece had jammed the lever. That's why nothing was engage as the gear moved. I took the broken piece out so now the shifter is working again. However, the lever now relies 100% on gravity to drop down so I expect any friction/gum would cause to the shifter to stop enaging again. I will use it temporary until I can get a new one and make sure to keep it clean. Interestingly, the shifting is now 100% quiet. There is no clicking sound at all. Very strange.