Trigger That Will On Updating Table Order And Changing Status To GoodsReceived

my simplified database schema is:

Order
OrderID
Status
OrderItems
OrderID
EAN
Amount
Store
EAN
Amount

now,I need trigger that will on updating table Order and changing status to "GoodsReceived" increase amounts in Store according to values in OrderItems.

create or replace trigger order_received_trigger
before update
on Order
for each row
begin
if (:old.status=4 and :new.status=1) then
/*
select ean, sum(amount)
from OrderItems
where OrderID=:old.OrderID
group by ean;
*/
end if;
end;

but now i dont know how to apply that select on table Store.