"Your vehicle is not responding" - Pixhawk 4 can't connect QGC

Hi everyone!

When I connect Pixhawk 4 (FMU v5) to computer with USB cable, QGroundControl shows message like this. Pixhawk 4 cannot connect to QGroundControl.

But I can upgrade firmware for Pixhawk4 from QGC. It has detected my device.

I tried changing the cable, and switching to another computer, but it still is not working

This is the video I recorded about my error

First step is to stop using an ancient version of QGC. Update to the latest Stable or Daily build.

Ohhhhhhhh, i fixed it.

how did you solve it