Contentful Delivery API - Cannot create new instance of custom model

Question

I have some content types defined in a contentful space and I am trying to fetch some content I've created.

These are the contentTypes I've created:

{
  "name": "Configuration",
  "description": "configuration",
  "displayField": "name",
  "fields": [
    {
      "id": "name",
      "name": "Name",
      "type": "Symbol",
      "localized": false,
      "required": true,
      "validations": [
        {
          "unique": true
        }
      ],
      "disabled": false,
      "omitted": false
    },
    {
      "id": "pages",
      "name": "Pages",
      "type": "Array",
      "localized": false,
      "required": true,
      "validations": [],
      "disabled": false,
      "omitted": false,
      "items": {
        "type": "Link",
        "validations": [
          {
            "linkContentType": [
              "Page"
            ]
          }
        ],
        "linkType": "Entry"
      }
    }
  ],
  "sys": {
    ...
    }
}

{
  "name": "Page",
  "description": "Page",
  "displayField": "name",
  "fields": [
    {
      "id": "name",
      "name": "Name",
      "type": "Symbol",
      "localized": false,
      "required": true,
      "validations": [
        {
          "unique": true
        }
      ],
      "disabled": false,
      "omitted": false
    },
    {
      "id": "title",
      "name": "Title",
      "type": "Symbol",
      "localized": true,
      "required": true,
      "validations": [],
      "disabled": false,
      "omitted": false
    },
    {
      "id": "shortTitle",
      "name": "Short title",
      "type": "Symbol",
      "localized": true,
      "required": true,
      "validations": [],
      "disabled": false,
      "omitted": false
    },
    {
      "id": "description",
      "name": "Description",
      "type": "Symbol",
      "localized": true,
      "required": true,
      "validations": [],
      "disabled": false,
      "omitted": false
    },
    {
      "id": "sections",
      "name": "Sections",
      "type": "Array",
      "localized": false,
      "required": true,
      "validations": [],
      "disabled": false,
      "omitted": false,
      "items": {
        "type": "Link",
        "validations": [
          {
            "linkContentType": [
              "Section"
            ]
          }
        ],
        "linkType": "Entry"
      }
    }
  ],
  "sys": {
    ...
  }
}

{
  "name": "Section",
  "description": "section",
  "displayField": "name",
  "fields": [
    {
      "id": "name",
      "name": "Name",
      "type": "Symbol",
      "localized": false,
      "required": true,
      "validations": [
        {
          "unique": true
        }
      ],
      "disabled": false,
      "omitted": false
    },
    {
      "id": "provider",
      "name": "Provider",
      "type": "Symbol",
      "localized": false,
      "required": true,
      "validations": [
        {
          "in": [
            "1",
            "2",
            "3"
          ]
        }
      ],
      "disabled": false,
      "omitted": false
    },
    {
      "id": "maxDisplayLimit",
      "name": "Max display limit",
      "type": "Integer",
      "localized": false,
      "required": true,
      "validations": [],
      "disabled": false,
      "omitted": false
    },
    {
      "id": "productList",
      "name": "Product IDs",
      "type": "Array",
      "localized": false,
      "required": false,
      "validations": [
        {
          "size": {
            "min": 1,
            "max": 50
          }
        }
      ],
      "disabled": false,
      "omitted": false,
      "items": {
        "type": "Symbol",
        "validations": []
      }
    }
  ],
  "sys": {
    ...
  }
}

And my Java code to fetch them:

client = CDAClient.builder()
                    .setSpace(space)
                    .setEnvironment(environment)
                    .setToken(accessToken)
                    .build();

client.observeAndTransform(Configuration.class)
                .withLocale(locale)
                .include(MAX_DEPTH)
                .all()
                .blockingFirst();

and I've modeled such contentTypes like:

@TransformQuery.ContentfulEntryModel("Configuration")
public record Configuration(@TransformQuery.ContentfulField String name,
                                                  @TransformQuery.ContentfulField List<Page> pages) {
}

@TransformQuery.ContentfulEntryModel("Page")
public record Page(@TransformQuery.ContentfulField String name,
                                         @TransformQuery.ContentfulField String title,
                                         @TransformQuery.ContentfulField String shortTitle,
                                         @TransformQuery.ContentfulField String description,
                                         @TransformQuery.ContentfulField List<Section> sections) {
}

@TransformQuery.ContentfulEntryModel("Section")
public record Section(@TransformQuery.ContentfulField String name,
                                            @TransformQuery.ContentfulField String provider,
                                            @TransformQuery.ContentfulField Integer maxDisplayLimit,
@TransformQuery.ContentfulField List<String> productList) {

}

When the code reaches the .observeAndTransform method I always get:

Cannot create new instance of custom model

I've also tried to remove everything a part the name of the Configuration contentType. I've also double-checked all the contentTypes ids and contentField ids to ensure the mapping was correct. Anyone has an idea?