Custom values not dropping when ticket is updated. Suggestions?

I am having an issue with custom field values being added to a ticket and
not dropping after a value should replace it this happens even after the
custom value itself has been removed from the table.

example:
ID Description Custom Value
11900 Amendment flagging on Legal projects ABS, IS&T, Move to IS&T
11905 Search Window Enhancements ABS, Move to IS&T

ABS has been removed from the custom value table.
IS&T has been removed from the custom value table.

Now when I run a query on the SQL database I still get the values present on
each ticket. I need to remove those values… Suggestions?

Do I need to have my DBA run a DTS job to remove the string values? Would
that work?

-Mark Grob