On my Windows computer, the function keys on my K series keyboard do not work, and Windows and Alt keys are switched. Please help.

Please check if the system toggle is on the "Windows" mode to match your device. To switch between function and multimedia keys (F1-F12), you can try:

For Windows: Hold fn + X + L for 4 seconds to switch

For Mac: Go to system settings ➡️ Keyboard ➡️ enable the function keys

*For F5 and F6 as function keys, press fn + K + C for 4 seconds and use the same shortcuts to switch.

(Refer to Keychron K3 User Manual for more info.)