check to see if specific record already exists

I have a registration table (Coordinator Registrations) with the following fields: Fname Lname District. I need to allow only one registration per District, so I need to check the table to see if anyone has already registered with that District. I am using AspRunner Pro 7.2

Here is the code I am using in the "Before Record Added" event page and it isn't working even though I have a District with the same name already in the table. No message is produced. District is a text field. Can anyone please tell me what I'm doing wrong. Thank you for any help.
dim rsDistrict

set dal_table=dal.Table("Coordinator Registration")

set rsDistrict = dal_table.Query("District='" & values("District") & "'","")

if not rsDistrict.eof then
Response.Write "This school district is already registered."

beforeadd = false

else

BeforeAdd = true

end if