Error when creating an index from a data source in azure cognitive search

I was recently tasked with indexing our Azure Blob Storage account (1.2tb). I am currently using the free version of Cog. Search (50mb storage limit). The issue I'm having is after I import data and create an indexer I get the following

Import configuration failed, error creating Index
Error creating Index: ""

What causes the issue to arise and how do I fix it? Is it a problem that I'm using the free version and so the storage isn't enough?