Try the below steps and check if it helps fix the issue:
- Connect both of the USB plugs to working ports on your PC
- Try connecting different devices to the passthrough
- Update the device's firmware
Download and install Logitech G-Hub (Available here: https://support.logitech.com/software/lghub)
Launch the software, select the keyboard from the home screen then go to Settings
If a firmware update is available, a Blue "Update" button would appear under the firmware version on the top right corner of the screen
- Test on another computer and check if the issue persists.