Just installed a new light near an existing one but one stays on, any help?
You have a wire crossed. Typical series would be black to white from one light to the next, and white all the way through the series. 1st light: white wire from switch continues to the 2nd light, the black wire on the light is connected to the black wire from the switch. 2nd light: white wire from 1st light is connected to the black wire of the 2nd light and the white wire on the second light is connected to the white wire from the switch.

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