title: Make Customer Email Field Unique
body: <p>is there a way to make the account email unique in Acumatica Customer?
  I already tried the Duplication Validation in Customer Managements Preference but it seems that it doesn't work on Customer.</p>
  <p>I am thinking if it can be done on Customization Project, though I have still no idea on that part.</p>
  <p><a href="https://i.stack.imgur.com/l2bSK.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/l2bSK.png" alt="enter image description here" /></a></p>