Hi Iris,
This issue normally occurs when the bluetooth driver is not compatible with Windows 8.
Let's uninstall the Bluetooth driver from the device manager and install the latest driver in compatibility mode and check.
Step 1: Uninstall and Reinstall Bluetooth Driver.
Please follow the steps given here to uninstall and then reinstall the Bluetooth driver.
a. Press Windows key +Xkey when you are at desktop.
b. Select Device Manager.
c. Find and double-click Bluetooth driver from the left panel to uninstall
d. Right-click the device, and click Uninstall.
e. Windows will prompt you to confirm the device’s removal. Click OKto remove the driver.
f. After the uninstallation is complete, reboot your computer as soon as possible.
Step 2:
Follow these steps to install the drivers in compatibility mode.
a. Download the drivers from the manufacturer’s website.
b. Right-click on the driver and click on properties.
c. Click on the ‘compatibility’ tab and check the box "Run this program in compatibility mode for” and select Windows 8 operating system from the drop down.
d. Click on ‘Apply’ and click ‘OK’ and run the file to install it.
Hope this information helps.