How should you address someone with MBE following their name?
The MBE, and the OBE, are honours which do not carry a title. They are Mr, Ms or Mrs. in writing and “Sir” or “Madam’ when addressing them in person, if you don’t know them. If you know them then you might be permitted to use their first name. Otherwise after the first “Sir” or “Madam”, I think it would be normal to call them Mr XYZ or Miss ABC, etc.