i forgot my office 2019 product key

For Office 2019, the product key itself usually is not needed again once it has been redeemed, because the license is tied to the Microsoft account used during setup.

Use these steps to recover and reinstall without the key:

1. On the PC, go to https://account.microsoft.com/services and sign in with the same Microsoft account that was used when Office 2019 was first activated (the email address used at purchase/activation).
2. Under Services & subscriptions, look for the Office 2019 license.
3. Select the Install button next to Office 2019 to download the installer, then run it and follow the prompts. Activation will use the Microsoft account automatically; no product key is required.

If the product key was never redeemed to a Microsoft account and cannot be found, or if there are issues with the key not working, contact the seller for assistance or a refund, as keys sold separately from the software are often fraudulent.

If additional help with a missing or non-working product key is needed, contact Microsoft support via the Microsoft support page.

References:

• Where to enter your Office product key
• Find your Office product key
• How to reinstall Office & Student 2019 - Microsoft Q&A