What could be the potential reasons for the fatal error "Interface 'User\Auth\DbBcryptAdapterInterface' not found" in a PHP project?

The fatal error "Interface 'User\Auth\DbBcryptAdapterInterface' not found" indicates that the interface DbBcryptAdapterInterface is missing in the User\Auth namespace. To solve this issue, you need to make sure that the interface is properly defined in the correct file and namespace. Check for any typos or missing files that could be causing this error.

<?php

namespace User\Auth;

interface DbBcryptAdapterInterface {
    // Interface methods
}

// Rest of the code