Did you set the item up with limits?  If you set limits up then it will stop at that line and not allow any additional amounts to be reimbursed.  You can deal with a monthly dump in and a yearly top limit or you can set the whole limit in and let them spend it all at one time and hope they don't quit before the end of the year.  I have done this with many types of deductions and garnishments, it keeps us all in line and on track.