Please consider watching this video before continuing: https://kb.policypak.com/kb/article/961-using-email-long-codes/
Next, PolicyPak doesn’t have an “API integration” with Servicenow, but you can make a nice workflow with PolicyPak Least Privilege Manager and ServiceNow or whatever help desk system you are using.
Basically, you configure PolicyPak Least Privilege Manager’s Email Admin Approval method to go to your inbox of Servicenow.

Then have someone on your Service desk use the Admin Approval tool to generate the response. Click the magic "@" button in the tool to automatically create the email. The only thing that needs to be entered in is the TO: field.

Additionally, if you want to give your end-users tips on what to do, you can add URL links which appear like this to the end user.

Setting this up is as easy as specifying a URL for them to click upon in the Custom message location in the Admin Approval policy.