If you encounter any issues with your product key, there are several troubleshooting steps you can try:
If you've purchased Office 2019, you can find your product key in the following locations: microsoft office version 18.1903 product key
Be cautious of websites offering "free" product keys for version 18.1903. These are often unauthorized "Generic Volume License Keys" (GVLK) intended only for large organizations using KMS activation and will not work for personal retail copies. If you encounter any issues with your product