Not possible to add a new item to a new created doctype

Hi

I just created a new doctype.
When i load the itemlist of this doctype, i can’t add a new one, the button is missing.

How can i resolve that?

Check the Permissions section for that doctype and see if you have given the Create permission to the role you have

If not, you can add it in the doctype or from the Role Permission Manager.

I am member of the system manager group, and this group has the correct permissions.
After logging off and on again, the button appeared.

Go to Roll Permission Manager, Restore Original Permissions or Add a User(default user is Administrator) and give Permissions.