REPEATABLE READ wrong session fails

[RunningJon]

--Session 1
INSERT INTO postgresqlkeyvalue002 (id, name, age, language) VALUES ('id01','Sumeet', 35, 'TestLanguage');
BEGIN; 
SET TRANSACTION ISOLATION LEVEL REPEATABLE READ;
UPDATE postgresqlkey value002 SET name = 'Sumeet Kumar' where id = 'id01';
select pg_sleep(15);

--Session 2
BEGIN; 
SET TRANSACTION ISOLATION LEVEL REPEATABLE READ; 
UPDATE postgresqlkeyvalue002 SET name = 'Sumeet Kumar1' where id = 'id01';
COMMIT;
SELECT * from postgresqlkeyvalue002;

--Session 1
SELECT * from postgresqlkeyvalue002;
COMMIT;
SELECT * from postgresqlkeyvalue002;

Results
Session2: Sumeet Kumar1
Session1: Operation failed. Try again.: Unknown transaction, could be recently aborted: f976e6aa-1893-4c4b-b4e0-72e8d1985b5f

Session2: Operation failed. Try again.: 48b9119e-9c6b-488f-b975- c76ea8824061 Conflicts with higher priority transaction: a154c821- 03d4-4897-a278-2f3baedd4e4b
Session1: Sumeet Kumar

Expected Behavior

• Session2 should wait until Session1 either executes COMMIT or ROLLBACK.
• On COMMIT of Session1, Session2 should fail because it couldn't serialize the access.
• On ROLLBACK of Session1, Session2 should be allowed to continue