I'd suggest you raise it to Microsoft directly for such bug.
Please contact your admin/IT department create a support ticket via Microsoft 365 Admin Center> Support> New service request. Support team there will have the correct channel and resources to help you investigate more and find what exactly the reason has caused this situation.
Get support - Microsoft 365 admin | Microsoft Learn
About how to find the admin in your organization, you can refer to How do I find my Office 365 admin
If the issue comes from an update. You may try rollbacking office update as workaround and wait Microsoft fix it.
ODT tool
How to revert to an earlier version of Office - Microsoft Support
Or CMD
- Start an Office application (such as Excel), and then select File > Account. select Update Options > Disable Updates.
- Type cmd on the start menu, right click on the Command Prompt, choose Run as Administrator
- Copy/paste these two commands one at a time and press enter
cd %programfiles%\Common Files\Microsoft Shared\ClickToRun
officec2rclient.exe /update user updatetoversion=16.0.17628.20164
Here is version history. Change the 16.0.17628.20164 to the version number based on your update channel.
Update history for Microsoft 365 Apps (listed by date) - Office release notes | Microsoft Learn