Forms :: Automate Check Number Programmatically

I have a Paycheck form with a subform on it. The goal is to not have to click on the check field for every paycheck, instead use a Batch procedure. When you click in the subform (field) (CCheckNo) which gets the focus by default it advances to the next check number and performs other code operations. If you have a lot of checks this is not very user friendly. I created a command button on the subform to try and auto ate this process. Below is the code for this. It gives no errors but does nothing. The db is very complex. The form opens to the first record but can't be sure when the user could run the Batch procedure.

The idea was to try and use the OnClick procedure to run the event code. The field in question is CCheckNo which advances the check number.

frmBonusReimbursementChecks is the Main form.
(Check) form is a Subform
CCheckNo field gets focus on Load which is the Subform.

Code Below is on a Command Button on the Subform.

If MsgBox("Are you sure you want to Assign All Checks?", vbYesNo, "All Checks Confirmation") = vbYes Then
End If
If IsNull(Me.CCheckDate) Then 'If no Check Date, Assign One.
Me.CCheckDate = Date
End If
If IsNull(Me.[CCheckNo]) Then 'Advance to the next available Check Number.
Me.CCheckNo = Next_Custom_Counter

[code]....