I understand that your tablet is not getting recognized by the computer.
1. Do you get any error message when you connect the tablet to the computer?
2. What is the make and model of the Tablet?
3. Have you tried to connect the tablet to different USB ports?
4. Have you made any recent changes to the computer
I suggest you to run the following steps and check if it helps.
I would suggest you to run “Hardware and Devices” troubleshooter to diagnose the exact issue. The hardware and devices troubleshooter can detect and fix errors and incorrect settings in devices. You can refer these steps
to run this troubleshooter:
a. Press “Windows key + W”.
b. Type “Troubleshooting” without quotes in the Search box and hit enter.
c. Select “Hardware and Sound” from the Troubleshooter Window.
d. Select “Hardware and Devices” under Devices option.
e. Follow the On Screen instructions.
I suggest you to logon to the Tablet manufacturer website and install the latest driver for the device from the website.
You can also refer to the article mentioned below for more information.