problem with count and sum

Hello. I have some difficulty when I use the following query. I have a problem with count and sum.
The joins are all correct.

select s.id, s.PromoTitle, count(distinct sc.id),sum(trx.amount)
from silver s
join interest i on s.Id = i.silverId
join customertransaction trx on i.Id = trx.InterestId
join silvercertificate sc on i.Id = sc.InterestId
where i.SystemId='silvers.gr' and i.StatusCode in (301,302,312) and sc.StatusCode in (600,601,612,602) and trx.StatusCode IN (401,1001,200,201)
group by s.id;

Code (markup):

The problem is when I use the silvercertificate table although it shows me the correct count(distinct sc.id) it does NOT show me the correct the other table customertransaction sum(trx.amount).
And unfortunately I have to use 2 queries which after I join.
there is some problem with count and sum but I can not find them.
Also the group by I have tried many other variables but it does not work.

I have tried and other solution with nested select but still it not brings me the correct results