HA hook with mysql backend not working

Hello, I Have problem with HA (in my case hot-standby). Server is unable to sync leases.

2020-09-25 09:51:32.806 DEBUG [kea-dhcp4.dhcpsrv/34387.140540437956480] DHCPSRV_MYSQL_GET_ADDR4 obtaining IPv4 lease for address 100.104.3.2
2020-09-25 09:51:32.806 DEBUG [kea-dhcp4.dhcpsrv/34387.140540437956480] DHCPSRV_MYSQL_UPDATE_ADDR4 updating IPv4 lease for address 100.104.3.2
2020-09-25 09:51:32.806 WARN  [kea-dhcp4.ha-hooks/34387.140540437956480] HA_LEASE_SYNC_FAILED synchronization failed for lease: { "cltt": 1600979173, "fqdn-fwd": true, "fqdn-rev": true, "hostname": "lt_pohorany_137_eap1", "hw-address": "c4:ad:34:ce:99:64", "ip-address": "100.104.3.2", "state": 0, "subnet-id": 10010400, "valid-lft": 432000 }, reason: unable to update lease for address 100.104.3.2 as it does not exist

mysql debug:

2020-09-25T07:51:32.806428Z	  370 Execute	SELECT address, hwaddr, client_id, valid_lifetime, expire, subnet_id, fqdn_fwd, fqdn_rev, hostname, state, user_context FROM lease4 WHERE address = 1684538114
2020-09-25T07:51:32.806540Z	  370 Execute	UPDATE lease4 SET address = 1684538114, hwaddr = 'ĭ4Ιd', client_id = NULL, valid_lifetime = 432000, expire = '2020-09-29 22:26:13', subnet_id = 10010400, fqdn_fwd = 1, fqdn_rev = 1, hostname = 'lt_pohorany_137_eap1', state = 0, user_context = NULL WHERE address = 1684538114 AND expire = '1970-01-01 01:00:00'

you can see it tries to match weird expire value '1970-01-01 01:00:00' but in database is:

mysql> SELECT * FROM dhcp.lease4 WHERE address=1684538114;
+------------+--------+-----------+----------------+---------------------+-----------+----------+----------+----------------------+-------+--------------+
| address    | hwaddr | client_id | valid_lifetime | expire              | subnet_id | fqdn_fwd | fqdn_rev | hostname             | state | user_context |
+------------+--------+-----------+----------------+---------------------+-----------+----------+----------+----------------------+-------+--------------+
| 1684538114 | ĭ4Ιd   | NULL      |         432000 | 2020-09-27 10:26:13 |  10010400 |        1 |        1 | lt_pohorany_137_eap1 |     0 | NULL         |
+------------+--------+-----------+----------------+---------------------+-----------+----------+----------+----------------------+-------+--------------+
1 row in set (0.00 sec)

Time is synchronized on both server. Same timezone selected.

Expected behavior

• Lease on remote site will update

Environment:

• Kea version: 1.8.0 + libdhcp_lease_cmds + libdhcp_ha
• OS: Debian x64
• Mysql server: 5.7.31 (Percona Server)