currval = currval+1

I have the following SQL statements

BEGIN;
-- account_id is a sequence
INSERT INTO account (name) VALUES ('test customer'||random()::text);
-- account_id is a foreign key
INSERT INTO account_detail (account_id,......) VALUES ((SELECT * from
currval('account_acccount_id_seq')), ........);
COMMIT;

ERROR: insert or update on table "account_detail" violates foreign key
constraint ...

I have executed the above without a transaction but in the same session, and the
issue was that the current value of the account points to the curval + 1

I have solved the above by subtracting 1 in the second insert statement. Why I
am having this problem, I have used current value many time and this is the
first time I have this behavior.

Regards