undefined method `name' for #
Means that Devise is looking for a model A that has a method or database column :name.
This will through an error unless you have a Model called A, with devise :registerable in the model definition, or is model A has no :name method of column.
Devise is typically used with a model, if you want two types of users, I suggest you make two separate models UserA and UserB and add Devise separately to each of them.