After creating a custom Doctype and adding it to a form, I can't save the form

Hello,
I tried creating a doctype to put a list of the items the supplier provides with the price he suggests. And I added it to the supplier’s form as a list.
But unfortunatly, I can’t save the items I add to the list.


App Versions

{
“erpnext”: “5.1.4”,
“frappe”: “5.0.34”,
“frappe_subscription”: “0.0.1”
}
Route

Form/Supplier/Darty
Error Report

Traceback (innermost last):
File “/home/frappe/press/benches/1507081350/apps/frappe/frappe/desk/form/save.py”, line 18, in savedocs
doc.save()
File “/home/frappe/press/benches/1507081350/apps/frappe/frappe/model/document.py”, line 239, in save
self.update_children()
File “/home/frappe/press/benches/1507081350/apps/frappe/frappe/model/document.py”, line 250, in update_children
d.db_update()
File “/home/frappe/press/benches/1507081350/apps/frappe/frappe/model/base_document.py”, line 272, in db_update
self.db_insert()
File “/home/frappe/press/benches/1507081350/apps/frappe/frappe/model/base_document.py”, line 245, in db_insert
set_new_name(self)
File “/home/frappe/press/benches/1507081350/apps/frappe/frappe/model/naming.py”, line 40, in set_new_name
frappe.throw(_(“{0} is required”).format(doc.meta.get_label(fieldname)))
File “/home/frappe/press/benches/1507081350/apps/frappe/frappe/model/meta.py”, line 97, in get_label
return self.get_field(fieldname).label
AttributeError: ‘NoneType’ object has no attribute ‘label’

Traceback (innermost last):
File “/home/frappe/press/benches/1507081350/apps/frappe/frappe/app.py”, line 51, in application
response = frappe.handler.handle()
File “/home/frappe/press/benches/1507081350/apps/frappe/frappe/handler.py”, line 69, in handle
execute_cmd(cmd)
File “/home/frappe/press/benches/1507081350/apps/frappe/frappe/handler.py”, line 92, in execute_cmd
ret = frappe.call(method, **frappe.form_dict)
File “/home/frappe/press/benches/1507081350/apps/frappe/frappe/init.py”, line 751, in call
return fn(*args, **newargs)
File “/home/frappe/press/benches/1507081350/apps/frappe/frappe/desk/form/save.py”, line 18, in savedocs
doc.save()
File “/home/frappe/press/benches/1507081350/apps/frappe/frappe/model/document.py”, line 239, in save
self.update_children()
File “/home/frappe/press/benches/1507081350/apps/frappe/frappe/model/document.py”, line 250, in update_children
d.db_update()
File “/home/frappe/press/benches/1507081350/apps/frappe/frappe/model/base_document.py”, line 272, in db_update
self.db_insert()
File “/home/frappe/press/benches/1507081350/apps/frappe/frappe/model/base_document.py”, line 245, in db_insert
set_new_name(self)
File “/home/frappe/press/benches/1507081350/apps/frappe/frappe/model/naming.py”, line 40, in set_new_name
frappe.throw(_(“{0} is required”).format(doc.meta.get_label(fieldname)))
File “/home/frappe/press/benches/1507081350/apps/frappe/frappe/model/meta.py”, line 97, in get_label
return self.get_field(fieldname).label
AttributeError: ‘NoneType’ object has no attribute ‘label’
Request Data

{
“type”: “POST”,
“args”: {
“doc”: “{"modified_by":"azza.jabnoun@aqylon.com","__ onload":{"contact_list":[],"addr_list":[]},"item":[{"docstatus":0,"doctype":"Itemsupp","name":"New Itemsupp 2","__ islocal":1,"unsaved":1,"owner":"azza.jabnoun@aqylon.com","parent":"Darty","parentfield":"item","parenttype":"Supplier","idx":1,"item_name":"g","item_price":"71"}],"naming_series":"SUPP-","creation":"2015-07-06 10:48:53.160776","doctype":"Supplier","modified":"2015-07-08 09:54:31.123010","communications":[],"accounts":[],"supplier_name":"Darty","owner":"azza.jabnoun@aqylon.com","docstatus":0,"supplier_type":"Distributeur","name":"Darty"," last_sync_on":"2015-07-09T14:51:36.460Z","__unsaved":1}”,
“action”: “Save”,
“cmd”: “frappe.desk.form.save.savedocs”,
“_type”: “POST”
},
“btn”: {},
“freeze”: true,
“freeze_message”: “Saving”,
“url”: “/”
}

Seems like you forgot to add a label in one of your fields.

Appear the same error when enter a wrong name in “Automatic Name” field while creating a doctype via UI.