Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
Hello, thank you for reaching out to Microsoft Q&A.
The installation issue is different from an activation issue. If you receive any error code or message when installing the Office apps on your iPad Air from the App Store, please share the exact error so we can further troubleshoot the problem.
If your license is no longer detected, you’ll see an activation error. However, if you’re having trouble with the installation itself, you may need to check your device or internet connection to help identify the root cause.
Have you tried restarting your iPad and then installing the Office apps from the App Store? Please try that and see if it works.
https://apps.apple.com/us/app-bundle/microsoft-365/id1450038993