Hello,
Okay I process some tests in order to better understand what's going on with your module, here my conclusions :
1. This module position is relative to your current template (yoo_sun)
2. For one url, it's impossible to have the subscriber menu module, even with full refresh page see my screenshot :
=> In the "classic" step by step checkout url, impossible to have your module (right part), beside this the url that start with
cart1 url, we are able to see the module...
This erratic display is quite difficult to understand for us, but as a guess I wonder, if at least we can't have some clue from the
template creator support as this position work only thanks to
yoo_sun.
Contact the template support to have more clues, and even maybe a solution, hoe this will help us to progress on your subject.
Regards