Please make sure you have the latest version of the Happiest Baby App. The latest is always available from the Apple® App Store or Google Play®.
If you need to reboot your SNOO, just unplug its power adapter from the wall outlet. Wait a few seconds, then plug SNOO back in. The SNOO Activity Button will flash white while rebooting. It may take several minutes before it glows the constant white light which means the reboot successfully finished.