You can facilitate a viewer password reset in the same way the viewer would do so themself.
In this case, go wherever you have placed your paid content. This does not have to be on the same webpage, even just copying and pasting the shared link of the paid content will do.
First, click the “Buy” button on the bottom right side of the paywall.
Next click “Forget Password?”
Enter the viewer’s email address and then click “Send”.
This will email the viewer a new password from the provided email address. Please make sure it’s not being blocked by spam filters or other settings.