Is this what you mean:
Code:
'form1
Private Sub t2_Click()
For Each obj In Application.CurrentProject.AllForms 'close all forms that opened
If obj.IsLoaded = False And obj.Name = "Form2" Then
DoCmd.OpenForm "Form2", acNormal
'flg = 1 'flag to show form2 need to be opened
Exit For
End If
Next
'Forms("Form2").Controls("cd").ListIndex = a + 1
Call Form_Form2.Combo1_Change 'Vlad March3/2020 -in form2 I changed the sub from Private to Public
End Sub
'form2
Public Sub Combo1_Change() 'if value of combo1 changed
Set db = CurrentDb
Set cdb = db.OpenRecordset("SELECT * FROM Table1 WHERE num = '" & Combo1.Value & "'", dbOpenSnapshot)
Me.t1.Value = cdb.alpha
End Sub
Cheers,