## Bug description

*Please describe.*  
- some datapoints show 0 but people will appear in modal

*If this affects the front-end, screenshots would be of great help.*  

## Expected behavior
- amount of people and datapoint should be the same


## How to reproduce

1. demo data clickhouse instance
2. go to retention trends for a day with some people


## Environment

- [ ] PostHog Cloud
- [ ] self-hosted PostHog, version/commit: _please provide_

## Additional context



#### *Thank you* for your bug report – we love squashing them!

posthog/queries/test/test_retention.py
person1 = person_factory(team_id=self.team.pk, distinct_ids=["person1", "alias1"])
            person2 = person_factory(team_id=self.team.pk, distinct_ids=["person2"])
            self._create_events(
                [
                    ("person1", self._date(0)),
                    ("person1", self._date(1)),
                    ("person1", self._date(2)),
                    ("person1", self._date(5)),
                    ("alias1", self._date(5, 9)),
                    ("person1", self._date(6)),
                    ("person2", self._date(1)),
                    ("person2", self._date(2)),
                    ("person2", self._date(3)),
                    ("person2", self._date(6)),
                ]
            )
            result = retention().run(
                RetentionFilter(