Integrating the Shellys into your home Wi-Fi network can sometimes be really frustrating. Several attempts are made, reset, new attempt, reset, new attempt, .... The game seems endless.
Often the problem sitting in front of the keyboard! 
Here are some ways to explain why WLAN integration failed:
- SSID incorrect -> upper and lower case note, literal error
- Workaround Problem Special characters: Copy SSID from router -> copy & paste
- Network key incorrect -> upper and lower case note, literal error
- Network ID incorrect -> IP - outside the home network address range, Network mask wrong or missing
- Gateway wrong or missing -> usual IP Router
- IP should be outside the DHCP range
- Radio frequency: 2.4 - 2.5 GHz -> 5.0 GHz Disable frequency in the router if necessary
- Connect mobile device (iOS / Android) to the 2.4 GHz network
- Router-settings:
- Wi-Fi security: Set to "Allow all new Wi-Fi devices"
- If you have a successful connection, you can reset this setting.
