Hi,

You can refer to the PDN article https://community.pega.com/sites/default/files/help_v718/procomhelpmain.htm on the requestor timeout.  In your case I think you need to review the below whether you need perform these;

avoid a user being prompted to authenticate again periodically
avoid a requestor being passivated
avoid a requestor lock timing out
avoid a browser interaction from timing out

The clipboard is not thread safe, prpc must serialize processing for one session/requestor. A browser may send multiple requests for same user session due to the core implementation of the UI (ajax and sections that load independently) or due to a user clicking or taking action, While your email process is running, every other request must wait to get requestor and clipboard access. prpc puts a time limit on a requestor for 120 seconds. For any interaction when 120 seconds is exceeded throws a "requestor lock exception" assuming that the server did not respond within 120 seconds and it is hung. Users(browser requestors) typically do not wait for more than 120 seconds for the server to respond and increasing this limit is typically not suggested/recommended.

Let me know if the above information helps.

Regards,

Basavaraj Kadakol