# Buggy code
def _validate_axis_equality(self, axis: int, force: bool = False):
    """
    Validates internal and external indices of modin_frame at the specified axis.

    Parameters
    ----------
        axis : 0 or 1
            Axis to validate indices along (0 - index, 1 - columns).
        force : boolean, default False
            Whether to update external indices with internal if their lengths
            do not match or raise an exception in that case.
    """
    internal_axis = self._frame_mgr_cls.get_indices(
        axis, self._partitions, lambda df: df.axes[axis]
    )
    self_axis = self.axes[axis]
    is_equals = self_axis.equals(internal_axis)
    if (
        isinstance(self_axis, DatetimeIndex)
        and isinstance(internal_axis, DatetimeIndex)
        and is_equals
    ):
        if getattr(self_axis, "freq") != getattr(internal_axis, "freq"):
            is_equals = False
            force = True
    is_lenghts_matches = len(self_axis) == len(internal_axis)
    if not is_equals:
        if not is_lenghts_matches:
            if axis:
                self._column_widths_cache = None
            else:
                self._row_lengths_cache = None
        new_axis = self_axis if is_lenghts_matches and not force else internal_axis
        self._set_axis(axis, new_axis, cache_only=not is_lenghts_matches)


# Traceback (Exception)
Traceback (most recent call last):
File "test.py", line 15, in <module>
print(f"modin:\n{modin_df.sum(min_count=1)}")
File "modin\pandas\base.py", line 3512, in __str__
return repr(self)
File "modin\pandas\series.py", line 307, in __repr__
temp_df = self._build_repr_df(num_rows, num_cols)
File "modin\pandas\base.py", line 108, in _build_repr_df
return self.iloc[indexer]._query_compiler.to_pandas()
File "modin\backends\pandas\query_compiler.py", line 191, in to_pandas
return self._modin_frame.to_pandas()
File "modin\engines\base\frame\data.py", line 1801, in to_pandas
"Internal and external indices do not match.",
File "modin\error_message.py", line 54, in catch_bugs_and_request_email
" caused this error.\n{}".format(extra_log)
Exception: Internal Error. Please email bug_reports@modin.org with the traceback and command that caused this error.
Internal and external indices do not match.

# Fixed code
def _validate_axis_equality(self, axis: int, force: bool = False):
    """
    Validates internal and external indices of modin_frame at the specified axis.

    Parameters
    ----------
        axis : 0 or 1
            Axis to validate indices along (0 - index, 1 - columns).
        force : boolean, default False
            Whether to update external indices with internal if their lengths
            do not match or raise an exception in that case.
    """
    internal_axis = self._compute_axis_labels(axis)
    self_axis = self.axes[axis]
    is_equals = self_axis.equals(internal_axis)
    if (
        isinstance(self_axis, DatetimeIndex)
        and isinstance(internal_axis, DatetimeIndex)
        and is_equals
    ):
        if getattr(self_axis, "freq") != getattr(internal_axis, "freq"):
            is_equals = False
            force = True
    is_lenghts_matches = len(self_axis) == len(internal_axis)
    if not is_equals:
        if not is_lenghts_matches:
            if axis:
                self._column_widths_cache = None
            else:
                self._row_lengths_cache = None
        new_axis = self_axis if is_lenghts_matches and not force else internal_axis
        self._set_axis(axis, new_axis, cache_only=not is_lenghts_matches)