BUG #15468: vacuum command returns ERROR: cannot freeze committed xmax

The following bug has been logged on the website:

Bug reference: 15468
Logged by: Andriy Bartash
Email address: banlex73(at)gmail(dot)com
PostgreSQL version: 10.4
Operating system: CentOS Linux release 7.5.1804 (Core)
Description:

Hello
I am running vacuum and getting
vacuum ntfn;
ERROR: cannot freeze committed xmax 614477059
----- in postgres log with log_error_verbosity =verbose
2018-10-29 23:36:02.982 UTC [23010] (user=barclays) (db=barclays)
(rhost=10.203.163.187) [vxid:193/3945120 txid:0] [SELECT] LOCATION:
exec_execute_message, postgres.c:2045
2018-10-29 23:36:05.721 UTC [32145] (user=postgres) (db=barclays)
(rhost=[local]) [vxid:272/1617334 txid:0] [VACUUM] ERROR: XX001: cannot
freeze committed xmax 614477059
2018-10-29 23:36:05.721 UTC [32145] (user=postgres) (db=barclays)
(rhost=[local]) [vxid:272/1617334 txid:0] [VACUUM] LOCATION:
heap_prepare_freeze_tuple, heapam.c:6769
2018-10-29 23:36:05.721 UTC [32145] (user=postgres) (db=barclays)
(rhost=[local]) [vxid:272/1617334 txid:0] [VACUUM] STATEMENT: vacuum
ntfn;

I found that error in my log 10 days ago.
What I checked be before I file this report:
1. Long-running transactions (nothing found)
SELECT pid, datname, usename, state, backend_xmin
FROM pg_stat_activity
WHERE backend_xmin IS NOT NULL
ORDER BY age(backend_xmin) DESC;
2.Abandoned replication slots:
Yes we have 3 physical replication slots and all are active. All slots
session were terminated and recreated automatically (didn't help)
select slot_name, active, slot_type, restart_lsn FROM pg_replication_slots
where slot_type='physical';
slot_name | active | slot_type | restart_lsn
-------------------------------------+--------+-----------+--------------
postgres_prd_europewest2_emeaprd0_2 | t | physical | A78/7A76A8A8
postgres_prd_europewest2_emeaprd0_0 | t | physical | A78/7A720000
postgres_prd_europewest3_emeaprd0_1 | t | physical | A78/7A69FE88

3. Orphaned prepared transactions:
SELECT gid, prepared, owner, database, transaction AS xmin
FROM pg_prepared_xacts
ORDER BY age(transaction) DESC;
gid | prepared | owner | database | xmin
-----+----------+-------+----------+------
(0 rows)

Thank you in advance
Andriy