title: How can I use a seller email address on my website instead of client-id
body: <p>I am developing a web application where  I need to allow some vendors using my application sell their services.</p>
  
  <p>I would like to integrate my app with PayPal express checkout. I ran into an issue where using express checkout requires the seller Client-ID.</p>
  
  <p>In my case I am only allowed to get the sellers PayPal email address and not their PayPal Client-ID. How can I use their email instead of Client-ID to use PayPal express checkout?</p>
  
  <p>Appreciate your help in advance</p>
  
  <p>Kazem</p>