Content-single.php inside my plugin

In case anyone will want to do this, this is what worked for me:

In my single-my_custom_post_type.php

I replaced this line:

get_template_part('content', get_post_format());

With this one:

include 'content-spp_service_provider.php';

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)