Hi I have a date field on my fieldset but after adding an item to the collection the field is not saving. Any thoughts?

sections:
  main:
    display: Main
    fields:
      title:
        display: Title
        type: text
        width: 75
        localizable: true
      slug:
        type: text
        width: 25
        display: Slug
      subtitle:
        type: text
        width: 75
        display: Subtitle
      website:
        type: text
        width: 25
        display: Website
        validate: url
      intro:
        restrict_assets: false
        type: redactor
        display: Intro
        width: 75
      date:
        display: Date
        type: date
        allow_blank: false
        allow_time: false
        require_time: false
        earliest_date: 'January 1, 1900'
        width: 25
      overview_image:
        container: main
        folder: realisaties/overview_image
        restrict: true
        max_files: 1
        mode: grid
        type: assets
        width: 50
        display: 'Overview Image'
      detail_image:
        container: main
        folder: realisaties/detail_image
        restrict: true
        max_files: 1
        mode: grid
        type: assets
        width: 50
        display: 'Detail Image'
      replicator:
        sets:
          one_image:
            display: 'One Image'
            instructions: 'One large image'
            fields:
              image:
                container: main
                folder: realisaties/bard
                restrict: false
                max_files: 1
                mode: grid
                type: assets
                display: Image
          two_images:
            display: 'Two Images'
            fields:
              images:
                container: main
                folder: realisaties/bard
                restrict: true
                max_files: 2
                mode: grid
                type: assets
                display: Images
          image_and_text:
            display: 'Image and text'
            fields:
              title:
                type: text
                display: Title
              text:
                restrict_assets: false
                type: redactor
                display: Text
              image:
                container: main
                folder: realisaties/bard
                restrict: true
                max_files: 1
                mode: grid
                type: assets
                display: Image
        type: replicator
        display: Replicator
      categories:
        taxonomy: categories
        type: taxonomy
        display: Categories
taxonomies: true
title: Project