OneDrive Admin Center is moving. Now you will find that in the SharePoint Admin Center.
Here is a description where to find OneDrive admin Settings.

Finally, Microsoft has put OneDrive (for Business) and its administration where it belongs. In the SharePoint Admin Center.
Because this has repeatedly caused confusion. Because OneDrive (for Business) is a SharePoint site collection, like other SharePoint sites. And that for every OneDrive (for Business) user.  To summarize general policies and settings for all OneDrive users, they used to be in the OneDrive Admin Center. And now in the SharePoint Admin Center.