My joycon work when connected to device but not wireless

There are few possibilities for what the issue(s) are with the symptoms you've outlined. You mention that the green LEDs are not lit when the controller is disconnected and that the controller is not detected by the console. If this is the case, the initial matter of concern is determining whether or not your Joy-Con's battery is functional. Disassemble your controller and check the connector and cables to ensure that there is no damage and that it is attached properly. If both of these possibilities are eliminated, it's worth considering the possibility that the battery itself is dead. You can confirm this by removing the battery from your other Joy-Con and installing it in the one with issues after ensuring that the connector and port are clean and there's nothing that may cause a short.

If you find that the Joy-Con is functional wirelessly after installing the other working battery, you have your solution. At this point, you should determine whether or not the battery charges when the Joy-Con is connected to the console. This can be observed in the controller menu. Your description indicates that your bottom ribbon cable is functional, but if the battery will not charge when connected, the bottom ribbon cable may be dirty, have slight damage, or be improperly seated in the best case scenario. The alternative possibility is a board issue, which would be a more complicated matter to resolve.

If you still find that the the lights on the side-rail of the controller do not function even despite the controller working, then it's likely that the upper ribbon cable is either damaged or is not attached properly. Check the ribbon cable connector. If it's properly seated, you'll likely need to order a replacement to resolve the issue. The upper ribbon cable is responsible for the green LEDs, wireless SYNC functionality, and the SL/SR buttons. These are not necessary for standard play unless the user plays using a single Joy-Con or uses the controllers in that capacity for multiplayer.