We have been using this product for a good year now without any problems.
The problem with the WLAN is that it only supports 2.4Ghz. With dual band routes, maybe set up a guest account with 2.4Ghz, that's how I solved the problem.

Disconnect the power supply and wait 10 seconds. Then plug it back in and press the big button on the robot for 5 seconds. The Wi-Fi connection no longer works for me and I only start the robot using the remote control. I must have saved money in the wrong place (product) :-)