Error: the ZABBIX database version does not match current requirements. Your database version: 5000000. Required version: 4000000. Please contact your system administrator

Cause of problem:
the current database version is inconsistent with the required database version
solution:
log in to the database and modify the mandatory value of the database version to 4000000

MariaDB [(none)]> use zabbix;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Database changed
MariaDB [zabbix]> select version();
+----------------+
| version()      |
+----------------+
| 5.5.68-MariaDB |
+----------------+
1 row in set (0.00 sec)

MariaDB [zabbix]> update dbversion set mandatory=4000000;
Query OK, 1 row affected (0.00 sec)
Rows matched: 1  Changed: 1  Warnings: 0

MariaDB [zabbix]> flush privileges;
Query OK, 0 rows affected (0.00 sec)

MariaDB [zabbix]> select version();

Restart ZABBIX server