Dynamic schema name

Btw, this is the error I get, when trying to pass the schema name in via function head parameter. My schema is called Account:

** (Protocol.UndefinedError) protocol Ecto.Queryable not implemented for Account of type Atom, the given module does not exist. This protocol is implemented for the following type(s): Tuple, BitString, Ecto.SubQuery, Ecto.Query, Atom