I’ve worked in Drupal once before and I had forgotten the most important thing to know…. manually clearing your site’s cache.
Basically this is a step you need to take when making a new template. In fact, if anything looks off with your drupal site, it could quite possible be the cache. (This is for people that set it up correctly, if you haven’t then your problem is probably something else)

So after you make the “node–contenttype.tpl.php” file in your templates folder, do the following steps:
1) go to “Configuration”
2) go to “Performance” (in the Development category)
3) click the “clear all caches” button

This solved my problem, hopefully this helped you too
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