PostgreSQL "ERROR: could not determine data type of parameter" Ruby exec

I am trying to execute a query that selects recipes that match a search term from user input stored in the query variable. This is the portion of relevant code:

class DatabasePersistence
  def initialize(logger)
    @db = if Sinatra::Base.production?
        PG.connect(ENV['DATABASE_URL'])
      else
        PG.connect(dbname: "recipes")
      end
    @logger = logger
  end

  def search_recipes(query)
    p "Query parameter is:"
    p query
    p query.class
    sql = <<~SQL
    SELECT * FROM recipes
    WHERE labels ILIKE '%$1::text%'
    SQL
    results = query(sql, query)
    # ... more code
  end

  def query(statement, *params)
    @logger.info "#{statement}: #{params}"
    @db.exec_params(statement, params)
  end

end

The following error is raised on when this line results = query(sql, query) is executed.

PG::IndeterminateDatatype at /search
ERROR: could not determine data type of parameter $1

Another post suggested adding an explicit type cast which is why I added the type cast. I could be doing it incorrectly. I also tried it like the following:

WHERE labels ILIKE '%text($1)%'
WHERE labels ILIKE '