Hi Patti. I'm Greg, an installation specialist and 8 year Windows MVP, here to help you.
Confirm it's not the mouse itself by trying it in another device to compare.
If it's wireless change the battery, make sure the On switch is set correctly underneath.
Try another USB port, does it make any sound and show activity in System tray at right end of task bar?
Go into the Device Manager, choose the Mouse device, on Driver tab see if Roll back is available and try that first. If not then try Uninstall, restart PC using keyboard to Ctrl Alt Del, on blue screen tab to Power Icon in bottom right, press Enter, arrow down to Restart, press Enter to restart to reinstall the driver.
I hope this helps. Feel free to ask back any questions and let us know how it goes. I will keep working with you until it's resolved.
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