it seems that your 'StaffIntials' field is a calculated field.
Check that the result is text, not number.
Backup your Database (if you have not done so, recently)
Open the Backup, Save As Clone (no records)
Open the Clone of the Backup and import the records from the Backup and Test.
If no joy...
Recover the Backup with the Recover Command under the File Menu.
Open the Recovered Backup and test
About the Recover Command
About the Save As Clone