Issue when login from Facebook: same username!!!!

Hi,

first of all thank you for this great plugin!

I’ve an issue:
if an user makes first registration from his facebook account where he has a generation of username like @name+surname (like @john_doe) and than another user, with same name and surname, tries to register, he will obtain the same username @john_doe… this is a problem… any way to obtain different automatic usernames in case one just exists linked to a different facebook ID??

Thank you in advance!

https://ww.wp.xz.cn/plugins/wordpress-social-login/