Issues connecting to Strava

[0x09AF]

I set up a new app in Strava and filled in user_id and secret in settings.ini but I have a hard time pulling Strava data. Docker logs show that the connection is indeed established, I can see API requests on Strava app's page, but Fitly doesn't display any info from Strava. Some of the logs:

fitly  | Unable to set attribute nickname on entity <Shoe id=g5815688 name='Whitin trail Barefoot'>
fitly  | Unable to set attribute retired on entity <Shoe id=g5815688 name='Whitin trail Barefoot' resource_state=2>
fitly  | Unable to set attribute converted_distance on entity <Shoe id=g5815688 name='Whitin trail Barefoot' resource_state=2>
fitly  | Strava connected
fitly  | 'NoneType' object has no attribute 'tokens'
fitly  | Spotify not connected
fitly  | Error in https://api.spotify.com/v1/me/top/tracks?time_range=medium_term&limit=10&offset=0:
fitly  | 401: Invalid access token

The app looks gorgeous on the screenshots, but when deployed the main page simply says "Provide oura credentials" and nothing else. I do not own oura, I just want Strava data.
I wonder if Strava has changed their API access rules since the last commit made to this app. Looking forward to using it.