See:
https://learn.microsoft.com/en-us/outlook/troubleshoot/user-interface/incorrect-folder-names
Can you rename the new "Inbox" folder then run resetfolders? if not, consider using mfcmapi as well ( Method in that doc)
Method 1 is the easiest so start there:
Use the /resetfolders switch to restore missing folders at the default delivery location. To do this, follow these steps:
Exit Outlook.
Run Outlook.exe /resetfolders.
Run Outlook.exe /resetfoldernames.