It's hard to identify the root cause of the NullPointerException since there is not enough information.
Based on the exception stack trace, the NullPointerException comes from your activity "runflowActionactivity". You can go to generated ra_action_runflowactionactivity_58efc1b6f854c94714f657cadaebe7ff.java (under your temp directory) and find line #379. The NullPointerException is from there.
You can also run your use csae and collect the tracer log.
It usually will capture the error and tell you where the error comes from.