Because you have Task 2 calling Task 3 on completion or exception, Task 2 could seem to be skipped at times. The reason this could happen is if something prevents Task 2 from running. I'm not sure how to guess what caused Task 2 not to start for you, but I'd say that it's impossible for Blue Prism to actually skip the task entirely. Most likely the app server sent instructions to the resource for Task 2 to begin after Task 1 and when it failed to start, Task 3 ran immediately after that.
An example of a time that this could happen is if you have Task 2 run on Runtime Resource 1 and Task 3 is supposed to start after Task 2 but this time on Runtime Resource 2. Regardless of whether Task 2 is successful, Task 3 will start on Runtime Resource 2. The reason this might happen is if Runtime Resource 1 is busy at the time the call is made for Task 2 to begin, such as an exclusive mode session running on Runtime Resource 1 already.
You may have found a bug, but verify that the schedule is still configured as it has been for weeks. Yesterday, I created a schedule and forgot to set Task 1 to call Task 2 on completion. It stumped me at first until I realized I just made a silly mistake and forgot to specifically choose the on complete and on exception drop downs for each Task.
It sounds like what I've described is not your issue, but it would be good to verify it again just in case Task 1 is calling Task 3 now.
Edit: I'd suggest changing the Login Agent action to not fail if the runtime resource is logged in already and then change your schedule so that it only runs the next task on completion.
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Dave Morris
3Ci @ Southern Company
Atlanta, GA
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Dave Morris, 3Ci at Southern Company