## 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=self.team, distinct_ids=["person1", "alias1"])
            person2 = person_factory(team=self.team, distinct_ids=["person2"])
            action = self._create_signup_actions(
                [
                    ("person1", self._date(0)),
                    ("person1", self._date(1)),
                    ("person1", self._date(2)),
                    ("person1", self._date(3)),
                    ("person2", self._date(0)),
                    ("person2", self._date(1)),
                    ("person2", self._date(2)),
                    ("person2", self._date(3)),
                ]
            )
            some_event = "$some_event"
            self._create_events(
                [("person1", self._date(3)), ("person2", self._date(5)),], some_event,
            )
            start_entity = json.dumps({"id": action.pk, "type": TREND_FILTER_TYPE_ACTIONS})
            result = retention().run(
                RetentionFilter(
                    data={
                        "date_to": self._date(6, hour=0),
                        "target_entity": start_entity,
                        "returning_entity": {"id": some_event, "type": TREND_FILTER_TYPE_EVENTS},
                        "total_intervals": 7,
                    }