ValueError: DateTime index is not continuous

[kosmylo]

Describe the bug
When I try to perform the step of preprocessing I am getting the following errror:

Traceback (most recent call last):
  File "/root/proloaf/./src/preprocess.py", line 87, in <module>
    dh.check_continuity(df)
  File "/root/proloaf/src/proloaf/datahandler.py", line 278, in check_continuity
    raise ValueError("DateTime index is not continuous")
ValueError: DateTime index is not continuous

To Reproduce
Steps to reproduce the behavior:

1. Clone the repository
2. Execute in the terminal `python3 ./src/preprocess.py -s opsd

Expected behavior
I would expect to finish the preprocessing step.