Aggregate functions not allowed in WHERE clause

I have two tables, Claims and Logs, and I need to fish in for the id of
any
claim who have into the logs anything into the fields invoices or
payments

I think the best way to do this is by mean of:

SELECT claim_id
FROM logs
WHERE (
sum(logs.invoices) > 0
OR
sum(logs.payments) > 0
)
GROUP BY claim_id

But Postgres claims "Aggregate functions not allowed in WHERE clause"

Anyone could help me to figure out this task please

Cordially
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