Password security action - need to input password for every file?

I regularly need to add password security to PDF forms so have been looking into creating an action to do this in Acrobat - which I've successfully done. 

However, if I start this action on a batch of files it still asks me to input the password twice for each form. Am I doing something wrong or missing a setting? Not having to input the password over and over really was the draw card for this action!

Alternatively - is there another way I can create a droplet or batch preset to run forms? I'm quite limited in my tech knowledge so bare that in mind when suggesting options.

Thanks in advance!