Upgraded from 5.4 to 6.0 database error

[morgan_p]

Hi all,

Looking for some support. We have upgraded from 5.4 to 6.0 but now displaying the below error when web browsing to the front-end;

Database Error;
The Zabbix database version does not match current requirements. Your database version: 5050109. Required version: 6000000.


[XXXXX@appliance /]# tail /var/log/zabbix/zabbix_server.log
21853:20220527:085621.079 SSH support: YES
21853:20220527:085621.079 IPv6 support: YES
21853:20220527:085621.079 TLS support: YES
21853:20220527:085621.079 ******************************
21853:20220527:085621.079 using configuration file: /etc/zabbix/zabbix_server.conf
21853:20220527:085621.096 current database version (mandatory/optional): 05050109/05050109
21853:20220527:085621.096 required mandatory version: 06000000
21853:20220527:085621.096 starting automatic database upgrade
21853:20220527:085621.097 [Z3005] query failed: [1061] Duplicate key name 'items_8' [create index items_8 on items (key_(768))]
21853:20220527:085621.097 database upgrade failed

Thanks in advance,

Regards,