Situation: The client uses Office 365. When he tries to use track changes, it says functionality currently limited track changes.
Troubleshooting: Please follow these steps to check the Office update.
- With the Word open, click File next to Home.

- Click on Account.

- Check the status of the Office Updates

or click Update Option>Update Now.

4. Restart the Word and try it.
Please view this step by step video: