Problems screen not display if not filtered by specific host

[sszabbix01]

If I click on the problems tab from the main dashboard nothing but a blank screen is ever displayed. The browser is trying to go to the following URL: https://<zabbix host>/zabbix.php?action=problem.view&ddreset=1. If I go into a specific host I am able to see problems just for that host.

Server has been running fine until this started happening

Server is running Centos 7 and Zabbix 4.2.6

[sszabbix01]

Fixed issue. It was due to a PHP memory limit set in /etc/httpd/conf.d/zabbix.conf. Changed "php_value memory_limit" to 512MB and restarted Apache.