AttributeError: 'NoneType' object has no attribute 'get'

I get this error every time I reload the Create X page. How can I solve it? What causes this error?

App Versions

	"frappe": "14.25.1",
	"shipper": "0.0.1"


Form/Shipper Order/new-shipper-order-1


Traceback (most recent call last):
  File "apps/frappe/frappe/", line 69, in application
    response = frappe.api.handle()
  File "apps/frappe/frappe/", line 54, in handle
    return frappe.handler.handle()
  File "apps/frappe/frappe/", line 45, in handle
    data = execute_cmd(cmd)
  File "apps/frappe/frappe/", line 83, in execute_cmd
    return, **frappe.form_dict)
  File "apps/frappe/frappe/", line 1607, in call
    return fn(*args, **newargs)
  File "apps/frappe/frappe/desk/form/", line 37, in getdoc
    doc = frappe.get_doc(doctype, name)
  File "apps/frappe/frappe/", line 1184, in get_doc
    doc = frappe.model.document.get_doc(*args, **kwargs)
  File "apps/frappe/frappe/model/", line 74, in get_doc
    return controller(*args, **kwargs)
  File "apps/frappe/frappe/model/", line 106, in __init__
  File "apps/shipper/shipper/shipper/doctype/shipper_order/", line 67, in load_from_db
    super(Document, self).__init__(
  File "apps/frappe/frappe/model/", line 102, in __init__
    if d.get("doctype"):
AttributeError: 'NoneType' object has no attribute 'get'

Request Data

	"type": "GET",
	"args": {
		"doctype": "Shipper Order",
		"name": "new-shipper-order-1"
	"headers": {},
	"error_handlers": {},
	"url": "/api/method/frappe.desk.form.load.getdoc"

Response Data

	"exception": "AttributeError: 'NoneType' object has no attribute 'get'"


load_from_db function need to define the field name before create page