Analysing pega alert log will give better insight about that.Since It is not good approach to share alert logs here so please raise an SR with GCS and attach pega rules and alert logs.
If your alert log contains a large number of PEGA0069 messages, a problem on the server, network, or client might be causing screens to take a long time to load. Using the message text, compare the load duration to the server duration to narrow down the issue to the server, client, or network. The action specified in the alert message can also help you determine which screen or action caused the alert. Other alerts that are triggered by this screen load have the same requestor ID and page load counter as the PEGA0069 alert. You can use this information to correlate those alerts to the PEGA0069 alert.It will be dependednt on some other alert.