Passing prefix to the Migrator results in error (Postgres)

[jk-lamb]

In the target up:

defmodule KantaTest.Repo.Migrations.UpdateKantaMigrations do
  use Ecto.Migration

  def up do
    Kanta.Migration.up(version: 4, prefix: "kanta")
  end

  def down do
    Kanta.Migration.down(version: 4, prefix: "kanta")
  end
end

returns:

12:34:39.843 [info] execute "  ALTER TABLE kanta.kanta_messages\n    ADD COLUMN IF NOT EXISTS searchable tsvector\n    GENERATED ALWAYS AS (\n      setweight(to_tsvector('english', coalesce(msgid, '')), 'A')\n    ) STORED;\n"
** (Postgrex.Error) ERROR 3F000 (invalid_schema_name) schema "kanta" does not exist
    (ecto_sql 3.12.1) lib/ecto/adapters/sql.ex:1096: Ecto.Adapters.SQL.raise_sql_call_error/1
    (elixir 1.18.3) lib/enum.ex:1714: Enum."-map/2-lists^map/1-1-"/2
    (ecto_sql 3.12.1) lib/ecto/adapters/sql.ex:1203: Ecto.Adapters.SQL.execute_ddl/4
    (ecto_sql 3.12.1) lib/ecto/migration/runner.ex:348: Ecto.Migration.Runner.log_and_execute_ddl/3
    (elixir 1.18.3) lib/enum.ex:1714: Enum."-map/2-lists^map/1-1-"/2
    (elixir 1.18.3) lib/enum.ex:1714: Enum."-map/2-lists^map/1-1-"/2
    (kanta 0.4.1) lib/kanta/migrations/postgresql/v04.ex:19: Kanta.Migrations.Postgresql.V04.up/1
    (kanta 0.4.1) lib/kanta/migrations/postgresql.ex:73: anonymous fn/4 in Kanta.Migrations.Postgresql.change/3