vendor not being able to register despite unique credentials

Describe the bug
as soon as you register the vendor an alert is prompted that already a vendor is registered with this email.

To Reproduce
Steps to reproduce the behavior:

Go to vendors
Click on add new
enter details
See error
Expected behavior
if there is an account on that mail it should be shown in the grid view

Screenshots
image

Desktop (please complete the following information):

OS: Windows
Browser Chrome
Version 122.0.6261.95 (Official Build) (64-bit)

The issue names no files or tests. Reproduce the problem through Vendors > Add new in Chrome, then locate the vendor registration flow and its grid behavior. Done means a vendor with unique credentials can register, while an existing email is handled according to the expected grid behavior.

Written by the indexing model from the issue text.