Harmony 890 Pro suddenly went dumb

I have a relatively new Harmony 890 that I haven't used very much because I had problems with other components in my system that I had to have replaced. (they didn't work correctly right out of the box, long story) I finally have my system back together and it has been working well and we were all very excited with the 890 Pro. I came home yesterday afternoon and the Harmony wouldn't control the system when I sat down with it. I putzed with it after going out to eat but never did get it to work. The battery had died the day before and my son in law had put it in the charger which is where I had gotten it from when I went to use it. Is there something I need to do to 'reactivate' it after charging? Is there a connect button on the remote somewhere? I noticed there is one on the IR extender but I couldn't find one on the remote itself. Finally, has anyone ever had a situation where it just seemed to 'forget' everything it had been programmed with? I can intermittently get it to turn On/Off the TV but that's it. Any suggestions for me?

Yeah it shows a full charge. Also, last night when I was messing with it I could push a button but there was no flash on the RF indicator of the extender showing that it received a signal.

I ended up doing yard work when I got home and didn't have any time to work on it tonight. I'll try to get back to it tomorrow.

That's exactly what I did and I'm back up and running. Thanks to all for their assistance.

Mike