Help IKEA tradfri

After update i can’t intergrade IKEA tradfri. I get this error message in logg. Any idea to fix the error?

Error executing service <ServiceCall configurator.configure: configure_id=1519963632-1, fields=security_code=D3mCmOJIvVelkkWq>
Traceback (most recent call last):
File “/srv/homeassistant/homeassistant_venv/lib/python3.6/site-packages/homeassistant/core.py”, line 1006, in _event_to_service_call
await service_handler.func(service_call)
File “/srv/homeassistant/homeassistant_venv/lib/python3.6/site-packages/homeassistant/components/configurator.py”, line 224, in async_handle_service_call
call.data.get(ATTR_FIELDS, {}))
File “/usr/local/lib/python3.6/asyncio/futures.py”, line 331, in iter
yield self # This tells Task to wait for completion.
File “/usr/local/lib/python3.6/asyncio/tasks.py”, line 244, in _wakeup
future.result()
File “/usr/local/lib/python3.6/asyncio/futures.py”, line 244, in result
raise self._exception
File “/usr/local/lib/python3.6/asyncio/tasks.py”, line 179, in _step
result = coro.send(None)
File “/srv/homeassistant/homeassistant_venv/lib/python3.6/site-packages/homeassistant/components/tradfri.py”, line 56, in configuration_callback
from pytradfri.api.aiocoap_api import APIFactory
File “/srv/homeassistant/homeassistant_venv/lib/python3.6/site-packages/pytradfri/api/aiocoap_api.py”, line 6, in
from aiocoap import Message, Context
File “/srv/homeassistant/homeassistant_venv/lib/python3.6/site-packages/aiocoap/init.py”, line 39, in
from .message import Message, NoResponse
File “”, line 961, in _find_and_load
File “”, line 950, in _find_and_load_unlocked
File “”, line 655, in _load_unlocked
File “”, line 674, in exec_module
File “”, line 779, in get_code
File “”, line 487, in _compile_bytecode
ValueError: bad marshal data (invalid reference)

The problem was that I was on wrong debian version. After flasing a old version off my hass everything works .