We recommend that you create a Staff profile specific to your phone and that you limit it to only accepting payments, by turning off access to refunds. You will still be able to login with your primary account email to complete refunds and we would recommend that you use this login in our web application.
To create a Staff profile, go to hq.payfirma.com, login and select Staff.
Once in Staff, select to Add Staff to create your phone profile.
Provide the information requested by the page and make sure to turn off the Refund permission.