In Frappe15, I can't add or remove a column in my own custom app

[nithishwar_s]

Already I have a custom app, and now I migrated to version 15 after that in my own app itself I can’t delete existing columns, and even if I add a new column it starts with “custom_field_name”.
@buildwithhussain @netchampfaris

[ahassoun]

You are in the Customize Form instead of edit DocType. You need to Edit DocType not Customize DocType