Business Standard with Exchange Plan 2 NOW only showing 100GB of email space

  FOR THE PAST 3 YEARS, we have 15 users with Microsoft Business Standard with 100GB of email storage space and 11 with Microsoft Business Premium with 100GB of email storage.   I have 1 Business Standard with Exchange On-line Plan2, and 1 with Exchange On-line Plan2.  Both have always jhad 150GB of usable mailbox storage.   Both users for several years, leading up to September 18, 2026 had over 100GB of mail in their mailboxes and had no problems sending or receiving email, ever.  THEN ALL OF THE SUDDEN on 9/18/2026, these 2 users with Plan 2 are no longer able to receive any email and it now shows their mailbox is full Even though checking active users details about mail for both of these users shows 150GB storage.  In investigating further, in the exchange area of the admin portal, checking mailboxes indeed both of these 2 USERS ONLY SHOW 100GB, which is the exact same as all my other users who are not paying for Exchange PLAN 2.  HOW DO I REPORT this to Microsoft?