Upload Images to S3 - MissingSchemaError: Schema hasn't been registered for model "UploadFile"

Hi all! I’m new to Strapi but I’m trying to add the built in image uploader component that uploads images to an AWS S3 bucket and stores the image urls in MongoDB (through strapi-hook-mongoose). I’m trying to store the image urls in a model through a column called “images” which is an array of url strings.

However when I visit the listings and edit page of the model that has the “images” column, i’m facing this error:

[2021-01-27T09:12:08.257Z] error MissingSchemaError: Schema hasn't been registered for model "UploadFile".
Use mongoose.model(name, schema)
    at new MissingSchemaError 
...

What would be causing this issue and what are some potential fixes? I’m currently trying to customize the built in ContentManager plugin (in extensions/content-manager/services/ContentManager.js and cms/extensions/content-manager/controllers) but with no luck so far.

Thanks in advance!

System Information
  • Strapi Version: 3.0.0-beta.17.5
  • Operating System: macOS Catalina 10.15.6
  • Database: Mongo
  • Node Version: >=10.0.0
  • NPM Version: >=6.0.0
  • Yarn Version: