User's recent images

The plugin is designed to “cache” the links to your images and only check for new images every 3 hours. You can adjust the time between updates on the plugin’s settings page, but I recommend using 3 to 5 hours. Retrieving new information from Instagram can slow down your website and it is best not to do it too often.
If you are still seeing the same images after an entire day, there might be something else going on. Has the plugin updated or are you still seeing the same 4 images?