553 Relaying disallowed - What is the best way to allow users to contact using contact form?

553 Relaying disallowed - What is the best way to allow users to contact using contact form?

I am a laravel developer and I have a contact form. In the contact form, users are supposed to enter their email address and a message. When they enter their message and email address, I should receive an email from THE USER who wrote the email. In other words, if they put " john@example.com" in the contact form, I should get a mail from " john@example.com".

This is what I want to achieve.

But I get a relaying disallowed message simply because I set up an SMTP using admin@mywebsite.com and the sender's email is something totally different.

How can I achieve this?

I have tried using gmail to send emails but when I get emails, the email address is the gmail authentication that I used, not the user who put their email in the contact form.

Thanks.