Bulk Upsert onConflict not working

Future<void> dbMethod() {
    return supabase.from('table').upsert([
      {
        'id': someValue,
        'entry_type': 'something',
      },
      {
        'id': otherValue,
        'entry_type': 'otherthing',
      },
    ], onConflict: 'id,entry_type');
  }