RC7620-1 do not respond to AT commands

Hello, I am working with an RC7620-1 connected to an MCU thru UART interface (all inside a more complex board with many other components and I/O). Now I have spent few days sending AT commands to the module and I don’t get any response.
Does anybody know what might be the problem?
I have followed the power up procedure, verified the Tx/Rx communication code and still cannot find a good reason for not getting answer from the module.
What I have assumed is that I can send AT commands by default using UART interface but have not found any documentation to confirm it.
I have access to UART Tx/Rx pins but I have not found the Windows 10 USB drivers to make tests using a serial communication application, so if anybody can provide the drivers or a link to it would be very helpful
Please, any help/suggestion would be greatly appreciated.

Hi migmel2006,

Welcome you to our community.
Do you know the firmware RC7620-1 version you are using?
You can try to download the Windows USB driver at the below link and retry.

Hello, thank you.
I’m not sure about the firmware version.
After installing this should I see the AT COM port in device manager ? Because I cannot see any COM port besides the one I’m connected to

Hi migmel2006,

Yes, you should see the AT Modems COM port in the device manager. You need to connect to the module’s USB port.