As of last night, February 23rd, the Garmin service changed and now ConnectStats receives Service Logic Error as Garmin is rejecting the current approach ConnectStats uses to access the Garmin web page information.
I am pushing a new version that fixes the issue, hopefully will be approved soon by apple,
As explained here, you can still access your activities by making sure you use the ConnectStats service, which is still working. For that follow instruction in the link and make sure you select for Garmin Source “All” or “ConnectStats”. This should let you access new activities properly.
Please note that if you enable the connectstats service for the first time or if you are a new user of the app, you will not get any activities prior to you registering for the service, as Garmin only sends new activities after you registered. I’ll see how to improve that or write about how to work around it later.
I’ll update further when I have time to properly investigate and see if there can be a workaround.
Sorry for any inconvenience, please check here again later for updates