processed_keys.add(alias or get_validation_alias(field))

    for key in received_params.keys():
        if key not in processed_keys:
            if hasattr(received_params, "getlist"):
                value = received_params.getlist(key)
                if isinstance(value, list) and (len(value) == 1):
                    params_to_process[key] = value[0]
                else:
                    params_to_process[key] = value