After you have assigned the license seat to yourself or another user in your organization (for Plus, Pro, Student, and Enterprise only), there are a couple of ways to activate your license depending on your network situation.
Resolution:
1. Launch the Unity Hub.
2. Click the account icon in the top left of the window and sign in to your Unity ID.

3. After you are signed in, click Preferences (cog icon).
4. Click Licenses > Add license.
5. Unity Plus, Pro, Student, and Enterprise subscription holders click Activate with serial number (i). Unity Personal (free) users click Get a free personal license (ii).
(i) For Plus, Pro, Student and Enterprise subscription holders, enter your serial number and click Activate license.
(ii) Unity Personal (free) users, read the Terms of Service, click Agree and get personal edition license.
Also Read : Unity Unable to Refresh License
Troubleshooting
- Close the Hub completely using the task manager (or similar).
- Using your file explorer, navigate to:
* Windows:C:ProgramData/Unity
* Mac:
Library/Application Support/Unity
and delete the .ulf file housed there.
- Launch the Hub again, ensuring you allow the Hub to make changes to your hard drive in the process.
- Reactivate your license following the steps outlined in the above article.
If this does not work for you, send your log files and screenshots of any errors received to the Customer Experience team.