After installing additional accessories such as the extension and/or the corner connectors, some users may find some parts of their LED strip malfunctioning. Either they are switched off or displaying a different colour compared to what has been set in the Near App. The usual cause of this is failure to properly connect the LED strips with the connectors or damaged connectors.
1. LED Strip may have been partially or fully disconnected from the connector.
Open the connector closest to the working LED strip and check if the copper points have come loose or detached. If they are, simply connect them and the lights will come back on. Otherwise, check to make sure that + and - signs on the LED Strip and the connector matches. + should be matched with +, - should matched with -.
2. Damaged Connector / Corner Strip.
Sometimes when attempting to loosen the connector pins in order to insert The LightStrip, users may have accidentally applied too much force such that it lacks a "snug-fit" which may have caused the connected light strip to either lose connection hence not being able to light up or display a different colour as set in the Near app. Another reason is by damaging the corner strip (the flexible "L-shaped" board) due to repeated attempts to secure it into the connector.
One way to fix the problem is to tinker with the flexible board by pressing it down or moving it slightly to see if the colour syncs back up. If it works, paste a sticky tape over it and observe for 5 to 10 minutes then try changing colours to see if the entire LightStrip is responding accordingly. If it does, just leave the tape on and you're set!
If the step above failed to work, either the flexible board or the 6-pin connector is damaged. Try replacing them with a spare one if you have any leftovers or purchase another set of corner connector kit. It should work after some trial and error.