Modules & VBA :: SQL Query To Set In Variable?

I have a form in which am gathering information from the user to populate a table(Customer Master List) and at the same time (btn_Copy_Click Event)transferring the info to another form(Case) populating another table(Customer_Call). It is working fairly well, My issue is that before transferring the info I need to run a check(SQL Query) to make sure the customer or actually the Well ID don't exist in the Customer_Call table. I am trying to do this in pieces .....

1) capturing the well_Id in a variable(WellID) in the first form and using that to build the sql string and query the Customer_Call table.

2)once that works place it in a if / else clause to copy or not with appropriate messages

With that I am stuck in step 1

It works up until Set rst = CurrentDb.OpenRecordset(strSQL) the i get Run-time error '3061' Too few parameters. Expected 1.

Code:
Dim WellID As String
Dim strModel As String
Dim strSQL As String
Dim rst As DAO.Recordset
WellID = Forms!f_Customer_Lookup.Well_ID
MsgBox WellID ' testing to see if it picks up the correct box in form
strSQL = "SELECT Customer_Call.[Cus_Well_ID] " & _
"FROM Customer_Call " & _
"WHERE Customer_Call.[Cus_Well_ID] = WellID;"
Set rst = CurrentDb.OpenRecordset(strSQL)
strModel = rst!Cus_Well_ID
rst.Close
MsgBox rst ' Testing to see if the strSQL captured the data
Set rst = Nothing
End Sub