White panels can have different causes. You can try these troubleshooting steps before reaching out to support.
Step 1: Power cycle your Nanoleaf panels by unplugging them from power for 10 seconds
Step 2: If the issue persists, disconnect the Controller or Power Supply and connect it to a different panel.
Step 3: If the panel continues to stay white, test out 1 or 2 more panels
Step 4: The last step is to perform a hard reset on the Controller/Control Square. How to do a hard reset.