[BUG] crossover function doesn't work anymore

[vimrc-sj]

Hello,

The bot works well until last week, I met this problem when I enable the crossover function in config.yml, for example, as below:

crossovers:
  std_crossover:
    - enabled: true
      alert_enabled: true
      alert_frequency: once
      key_indicator: ema
      key_indicator_index: 0
      key_indicator_type: informants
      key_signal: ema
      crossed_indicator: ema
      crossed_indicator_index: 1
      crossed_indicator_type: informants
      crossed_signal: ema

I keep on getting the error messages:

Exception in thread Thread-1:
Traceback (most recent call last):
  File "/usr/lib/python3.7/threading.py", line 917, in _bootstrap_inner
    self.run()
  File "app_core.py", line 100, in run
    self.behaviour.run(self.market_data, self.settings['output_mode'])
  File "/home/pi/git/Crypto-Signal-Core/app/behaviour.py", line 66, in run
    new_result = self._test_strategies(market_data, output_mode)
  File "/home/pi/git/Crypto-Signal-Core/app/behaviour.py", line 164, in _test_strategies
    new_result[exchange][market_pair]
  File "/home/pi/git/Crypto-Signal-Core/app/behaviour.py", line 369, in _get_crossover_results
    'result': crossover_dispatcher[crossover](**dispatcher_args),
  File "/home/pi/git/Crypto-Signal-Core/app/analyzers/crossover.py", line 42, in analyze
    combined_data = pandas.concat([new_key_indicator, new_crossed_indicator], axis=1)
  File "/home/pi/.local/lib/python3.7/site-packages/pandas/core/reshape/concat.py", line 298, in concat
    return op.get_result()
  File "/home/pi/.local/lib/python3.7/site-packages/pandas/core/reshape/concat.py", line 516, in get_result
    indexers[ax] = obj_labels.get_indexer(new_labels)
  File "/home/pi/.local/lib/python3.7/site-packages/pandas/core/indexes/base.py", line 3172, in get_indexer
    "Reindexing only valid with uniquely valued Index objects"
pandas.errors.InvalidIndexError: Reindexing only valid with uniquely valued Index objects

Could you help me check it? Thanks a bunch.