@nataliamartinstudio
It looks like you either have no or a wrong access token.
Please go to Semplice -> General Settings and setup your access token.
Error Message from Instagram:
[unex_ce_instagram id="content_jpxg68z0y" count="25" span="span2" is_fluid="no" remove_gutter="no" target="dribbble" random="disabled"][/ce_instagram]