Yeelight offline after few minutes

I bought a new Yeelight Smart LED Bulb Smart Lamp 1S/1SE Colorful. After adding the lights into the Yeelight app sometime later the devices are offline and i can’t control the lights anymore.

I connect the lights into 2.4 GHz and the WPA Mode is WPA2 (AES).

The region that i connect to is Frankfurt (it’s where I live)

My ID: 6480179695

Please advise me with a solution.

Regards

It is recommended that you use mi home to try the connection.