Mismatch between Looker Dashboard and BigQuery

Hi,
I have connected a BigQuery table to Looker, but the results are slightly different, while using the same formula in the field calculation. (no filters are applied in the table in the dashboard)

BigQuery Example Code:

select
count(distinct case when feature1 > 0 then user else null end) as users,
from table_name
where month_trunc_date = date("2025-06-01")

Looker example:
A table created with dimension the month_trunc_date and as calculated field:
count(distinct case when feature1 > 0 then user else null end)

The results of the two should be the same, but are not. 
In the meantime I noticed that a few Looker features were added recently (or updated), that caused some issues or inconsistencies to other dashboards.

Any explanations?
thank you
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