1. Please turn on your Gecho and key in this channel (do not press SET yet):

333 421 213 433

2. Afterwards, you should see orange LEDs glowing in this pattern:

If it looks different, press RST and repeat step #1. Otherwise, press SET button.

3. Finally, click or tap on LEDs on this picture, to lit them in a configuration, matching your real board. When finished, click "check".