Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
Dear Cris,
Thanks for detailed information.
The fact that "Microsoft 365 Apps for business" was installed yesterday could indeed be due to updates. Sometimes, updates can cause the installation date to change. Regarding the "Change" button not working, Please ensure you have administrative rights on the computer. Sometimes, the "Change" button won't work if you don't have the necessary permissions. However, If the Office installation is corrupted, the "Change" button might not function properly. In this case, you might need to use the Office Repair Tool or reinstall Office.
Please let me know if you are having any issue while re-installing the office apps by downloading the Office installer from the Microsoft website and run it to reinstall Office.
Have a great day and take care! 😊
Sincerely,
Naren | Microsoft Community Moderator