i installed  zabbix_server (Zabbix) 5.0.5 on centos 8 
everything is working fine 
but the agents cannot register on the server

telnet from host to Zabbix server is ok 
telnet from server to host is ok 

I have 4 servers with the same issue 
configuration on agent side is ok and hostname defined correctly same as in zabbix server

getting an error from agent log with same as attached
same error from the agent that on zabbix server