Android Question Strange exception - java.util.NoSuchElementException

private Sub ProblematicSub As ResumableSub
   

    Dim DB As clsDB
    Dim T As CustomType
   
    ProgressDialogShow2("...Calculating...", False)
    Sleep(0)
   
    DB.Initialize

    iMin = 999999
    iCantidadSeriesMaxima = 0
   
    For Each key As Int In Starter.Map.ListKeys
   
        T = Starter.Map.Get(key)
       
        Dim mTMP As Map
        mTMP = DB.LeerValores(T.ID, Global)
       
        If mTMP.Size > iCantidadSeriesMaxima Then
            iCantidadSeriesMaxima  = mTMP.Size
        End If
   
        If iVistaActual = Starter.Vista.Value And mTMP.GetKeyAt(0) < iMin Then
            iMin = mTMP.GetKeyAt(0)
        End If
           
        mValores.Put(T.ID, mTMP)


    Next
   
    ProgressDialogHide
    Sleep(0)
    Return Null
   
   
End Sub

If iVistaActual = Starter.Vista.Value And mTMP.GetKeyAt(0) < iMin Then
            iMin = mTMP.GetKeyAt(0)
        End If

If iVistaActual = Vista.Value Then
                For Each key2 As Int In mTmp.Keys
                    If key2 < iMin Then
                        iMin = key2
                    End If
                Next
               'in spite of the minimum value always comes at the first place (element 0), i didn't put a break because 1-there are always a few elements, 2-i can't assure that the map will be always iterated in a given order... or could I?
            End If