Access Form's textbox not showing value - ms-access

Question

I have an unbound textbox in form f_FeuilleBleue. In my code, I give it a certain value;
Debug.Print strAHNS '00 0AA 00-100 F TX-01
Form_f_FeuilleBleue.txt_AHNS = strAHNS
If I put a stopping point on the next line, the immediate window shows that
?Form_f_FeuilleBleue.txt_AHNS
answer: 00 0AA 00-100 F TX-01
However, I still see it as blank in my form. There is no data to be read!
How do I fix this? Is it an issue with screen updating? (I have nothing setting it to off) Maybe form updating? (I have a msgBox in the BeforeUpdate event but it doesn't go in that event)
EDIT - additional info:
When I open the form, there is no problem. I can change the value in the form or by code. However the issue only happens when the form is opened from a menu-style form. Code below. Even after the opening sub finishes, the textbox won't update (visually - it does in value). After testing I see that the Change and the Update event are NOT launched when changing the value of the textbox from another sub (Private subs may be the cause?) But why is it continuing to not show the values even after the subs end?
Could be very, very relevant to read but I'm not sure what to make of it: Obtaining textbox value in change event handler
Here is the code that opens the form:
Private Sub Command7_Click()
Dim strAHNS As String
Dim strquery As String
strAHNS = Replace(Mid(Me.Combo_Dessin2, InStr(Me.Combo_Dessin2, "=") + 1), "=", " ")
strquery = "[ID] = (SELECT Max([ID]) FROM [Feuilles])"
Debug.Print strquery
If (PremierAffichage) Then
DoCmd.OpenForm FormName:="f_feuillebleue", WhereCondition:=strquery
Else
MsgBox "Le projet ou dessin n'a pas été trouvé."
End If
End Sub
Function PremierAffichage() As Boolean
Dim rsFeuilles As DAO.Recordset
Dim rsProjets As DAO.Recordset
Dim strContrat As String
Dim strProjet As String
Dim strDessin As String
Dim sqlquery As String
Dim strAHNS As String
Dim strGroupe As String
Dim strMachine As String
If IsNull(Me.Combo_Dessin2) Or IsNull(Me.Combo_Projet) Or Me.Combo_Dessin2.Value = "" Then
PremierAffichage = False
Exit Function
End If
strProjet = Me.Combo_Projet
strAHNS = Me.Combo_Dessin2
strMachine = Mid(strAHNS, 4, 3)
strGroupe = Mid(strAHNS, 8, 2)
Debug.Print strProjet & " ** " & strAHNS & " ** " & strMachine & " ** " & strGroupe
sqlquery = "SELECT [AHNS], [Contrat], [No Projet], [EP (groupe)], [Type machine], [Mois] FROM [Feuilles]" 'WHERE [AHNS] = '" & strAHNS & "'"
Set rsFeuilles = CurrentDb.OpenRecordset(sqlquery)
sqlquery = "SELECT [Projet HNA] FROM [Projets] WHERE [Projet AHNS] = '" & strProjet & "'"
Set rsProjets = CurrentDb.OpenRecordset(sqlquery)
Debug.Print strAHNS '========================================--------
Form_f_FeuilleBleue.txt_AHNS = strAHNS ' this works in .value but not showing the result
DoEvents ' any changes from there on don't update the value visually
' ==========================================------
If rsProjets.RecordCount > 0 Then
rsFeuilles.AddNew
rsFeuilles![Contrat] = rsProjets![Projet HNA]
rsFeuilles![No Projet] = strProjet
rsFeuilles![AHNS] = strAHNS
rsFeuilles![Mois] = MonthName(Mid(Date, 6, 2))
If strMachine Like "[A-Z][A-Z][A-Z]" Then
rsFeuilles![Type machine] = strMachine
rsFeuilles![EP (groupe)] = strGroupe
End If
rsFeuilles.Update
PremierAffichage = True
End If
rsProjets.Close
Set rsProjets = Nothing
rsFeuilles.Close
Set rsFeuilles = Nothing
End Function

Answer 1

Assign your value to the active form instance (the open form) instead of to the form's class.
So assuming the open form's name is f_FeuilleBleue and you want to assign that value to the form's txt_AHNS control ...
'Form_f_FeuilleBleue.txt_AHNS = strAHNS
Forms!f_FeuilleBleue!txt_AHNS = strAHNS
Reference the form by its name as a member of the Forms collection.