Error "setState() called after Dispose()" in flutter

Question

Good morning, I’m getting the following error message on the flutter:

[ERROR:flutter/lib/ui/ui_dart_state.cc(177)] Unhandled Exception: setState() called after dispose(): _RelatorioScreenState#e8cd4(lifecycle state: defunct, not mounted)

It is not happening all the time, it is random, researching saw that a solution would be to check if it is mounted before doing setState, so I did it as follows:

if (mounted) {
    setState(() {
      dadosEntrada = dados;
    });
  }

But the problem persists. I have this problem in both calls where I use Setstate. The class is like this:

class _RelatorioEntradasState extends State<RelatorioEntradas> {
  var dadosEntrada = 0.0;
  var dataChart;

  @override
  void initState() {
    super.initState();
    Intl.defaultLocale = 'pt_BR';
    _generateData();
  }

  Future<void> _generateData() async {
    try {
      final dbHelper = new RelatorioProviderDB();
      dados = await dbHelper.getDataEntradasMes();
      if (mounted) {
        setState(() {
          dadosEntrada = dados;
        });
      }
      await _dadosChart();
    } catch (error) {}
  }

  Future<void> _dadosChart() async {
    try {
      final dbHelper = new RelatorioProviderDB();
      final dadosChart = await dbHelper.getDataEntradasChart();
      dataReceita = dadosChart;

      if (mounted) {
        setState(() {
          tamanhoLista = dataReceita.length;
        });
      }

      dataReceita.forEach((e) {
        data1.add(new LancEntradas(e['descricao'], e['valor']));
      });

      _seriesData = List<charts.Series<LancEntradas, String>>();
      _seriesData.add(charts.Series(
        domainFn: (LancEntradas lancEntradas, _) => lancEntradas.descricao,
       measureFn: (LancEntradas lancEntradas, _) => lancEntradas.valor,
        id: '1',
        data: data1,
        fillPatternFn: (_, __) => charts.FillPatternType.solid,
        fillColorFn: (LancEntradas lancEntradas, _) =>
           charts.ColorUtil.fromDartColor(Color.fromARGB(255, 128, 0, 0)),
      ));
    } catch (error) {}
  }

  @override
  void dispose() {
    super.dispose();
  }
 }