My subscriber is not getting the reset password/welcome email
Please install the email log plugin which will show you every email that is sent via WordPress on your site, including Leaky Paywall new subscriber emails. You can then check the email log to see if your site is sending the new subscriber email and which user they are being sent to. If the user is not receiving them in their inbox, have them check their spam folder.
Use A Service To Send Emails From Your Site
You may need to set up an SMTP plugin and use a service like Mailgun or Postmark and let it send the emails for you. It's not the plugin itself, but that your site’s server isn’t “optimized” to deliver transactional emails.
Here’s an article about the why and how. It's about email deliverability with Ninja Forms, but the same principles apply. Emails Not Working