I'm sorry about the issue. Since you've tried on multiple computers, this confirms either the camera's USB cable is bad, or the USB port on the camera is bad. You can get / try with another USB cable to confirm.
But if you have a memory card slot on any computer, then please take out the memory card from the camera, then insert it to the memory card slot on the computer and check.
If no, instead of getting another camera USB cable, I recommend to get an external USB memory card reader.
Please reply at the box below to continue. Thank you.