Missing variables for some tasks of process instance history

We are using the self-managed camunda-8 platform v8.1.1 deployed through docker run commands. We have frequently seen that for some of the tasks the variables are missing.

For the screenshot below, the variables for “Get LOS Push Dump” task are missing. There are many such tasks in this workflow that do not show up variables. I could not figure out any pattern in this. It would be great if someone could throw light on this.

Thanks.