Calls wrong image file path
You might simply be editing the wrong "display". Happened to me :)

If you have the Display Suite Drupal module installed, node types can each have several option sets (called "displays") how to display their fields, and a template or view then selects one of them to show the node. With the Taxonomy display Drupal module, the same is possible for taxonomies.

In these cases, you might simply be trying to adapt the image style setting in the wrong display. Check if you have a second line of tab-like options (starting with "Standard") for either nodes or taxonomies. In that case you have multiple displays for this node type / taxonomy, and you have to configure the image type for the right one.

You'll have to visit one of these admin menu items to check for displays:


"Structure → Content Types → [your content type] → Manage Display"
"Structure → Taxonomy → [your taxonomy] → Manage Display"