PC doesn’t detect the EG21-GL module on my custom PCB

IoT Modules LTE Standard Module
1

Hello, I designed a custom PCB based on the Quectel EG21-GL for the company I work for. I received the prototype board today and everything is working fine except for the USB interface. When I plug in the USB cable, the board powers up but my computer does not recognize the EG21—nothing appears in the Device Manager. I removed the TVS diode to test if that was the issue, but the problem persists. I’ve attached the schematic below.

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2

Dear Customer,

May I know if you are using right windows driver?
Can you check your windows driver?

Regards,
Fazrul Redzuan

3

Hello, the issue is not related to the driver, as the device does not appear as an unknown device in Device Manager.

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