I have a problem getting the panels working as they should on both my C420 camera's, first day the after installing the solar panels they worked perfectly fine. After two days both camera's didn't charge and the app said no panels installed (sunny day). The day after they showed up again charging fine (while it was cloudy). The day after that, only one panel was charging. Now at this moment both panels are not charging. I think Tapo needs to adres this issue with a proper firmware update because I read more people having the same issues! I checked the connectors on both my camera's and the way the panels are installed. After reconnecting the cables nothing changed. I wiped the panels with a soft cloth and made sure they are facing the right direction. All in all this is very inconsistent. All the tips provided by Tapo I tried. 

Edit:

So i disconnected the cable of the sonar panel  waited until the camera had dropped to 98% and than reconnected the cable. 

As I suspected the app wouldn't show the panel working.

But after checking in on the app after an hour or so my camera was at a full 100% charge.

So this means te panels are working properly but the app doesn't show it correctly!