1.Go to https://gateway.sdl.com/
2. Select "Trados Studio Licensing Help"
3. Select "Reset License"
4. Select - "Freelance - Single User License"
5. Read the steps then click on "Reset my License"
6. This will take you to your RWS Account - you will have to log in with RWS ID username and password
7. Under the Licenses tab find the Trados Studio Freelance license you need to reset
8. Click on the "Reset license" option found to the right of the license number
9. In the next window, click on "Reset License" again 
10. You will receive a message that the reset is successful
11. Wait for 30 minutes before attempting to re-activate your license
12. You can re-activate Trados Studio Freelance again with the same license code