Do While loop hangs - database

Question

The loop below hangs if the input fufills the Do...While condition.
This code is meant to first check if the entered product code in the combobox (Me!Combo_Product_number) exists in product code field of query Q_compliant_FCM_EU.
If it exists, it tests for compliance. The product is compliant if all its PURE_QP1 (which can be more than one for a particular product) is found in PURE_QP1 field of T_DOSSIER_FPL.
If at least one of them is not found, then it is not compliant.
Private Sub Command455_Click()
Dim db As DAO.Database
Dim rst As Recordset
Dim rst1 As Recordset
If Nz(Me!Combo_Product_number) <> "" Then
Set db = CurrentDb
Set rst = db.OpenRecordset("Q_compliant_FCM_EU", dbOpenDynaset)
Set rst1 = db.OpenRecordset("T_DOSSIER_FPL", dbOpenDynaset)
rst.FindFirst "[PRODUCT_CODE] = '" & Me!Combo_Product_number & "'"
If Not rst.NoMatch Then
Do While Not rst1.EOF
rst1.FindFirst "[PURE_QP1] = '" & rst.Fields("PURE_QP1") & "'"
If Not rst1.NoMatch Then
rst1.MoveNext
Else
MsgBox ("Product code is NOT compliant to FPL")
Exit Sub
End If
Loop
MsgBox ("Product code is compliant to FPL")
Else
MsgBox ("Product code is not available")
End If
End If
End Sub
What is wrong with the above code?

Answer 1

Use DLookup for such simple tasks, like:
Dim PURE_QP1 As Variant
If Nz(Me!Combo_Product_number) <> "" Then
PURE_QP1 = DLookup("[PURE_QP1]", "[Q_compliant_FCM_EU]", "[PRODUCT_CODE] = '" & Me!Combo_Product_number & "'")
If IsNull(PURE_QP1) Then
MsgBox ("Product code is not available")
Else
If IsNull(DLookup("[ID field of T_DOSSIER_FPL]", "[T_DOSSIER_FPL]", "[PURE_QP1] = '" & PURE_QP1 & "'")
MsgBox ("Product code is NOT compliant to FPL")
End If
End If
End If