If you completely stop the workflow, save it, and then restart it does the issue persist? If a workflow was running, then was paused, altered, and resumed, the previous underlying workflow job doesn't get changed and will still execute with the previous configuration. Performing a full restart clears the underlying job and refreshes it with the new execution criteria.
Just from what I'm seeing here, it's the only scenario that I can think of that would cause your workflow to kick off prior to the scheduled time.
Hi @Greeshma_Sampath1 - There are a couple of strange time entries in there. The first one is when the workflow ran at 02:31:51 PM - that's almost a 2 minute schedule delay. It could indicate your system is under large performance load.The 20 minute delay at 03:50:12 PM is pretty extreme though.
The late starts could also be related to other factors like @craigthonis mentioned or if a workflow killed the Campaign Jobs (operationMgt) workflow and required a restart.