If you replaced your Wi-Fi router, you may either:
- Set it up with the same SSID and password as your previous network. In that case, since lights already know this network, they will automatically reconnect and no further action will be required.
Use a new SSID and/or password, but then you will need to re-do the pairing of the lights in order to pass them the new credentials. Some settings of your devices may be reset to default (e.g. WiZ click, fading time...)