There is a reset button inside the battery door. Use a paper clip or similar object to press until the red LED is blinking 5 times.

The current version of Eve Motion supports Thread. This technology makes your smart home network more responsive, robust, and increases its reach – the only other thing you need is a home hub (Thread border router). Battery-operated Thread accessories, such as Eve Motion, represent endpoints in your Thread network. 

By contrast, mains-powered Full Thread Devices (or FTDs) that are always on, such as Eve Energy, Eve Light Switch or Eve Water Guard, can act as router nodes within your Thread network and relay data packets. So, the more of these Full Thread Devices (FTDs) you have in your network, the more stable and greater its reach becomes. Learn more