Please report your sync issues here: Individual missing activities, missing backlog (no activities prior to a certain date), etc…
I’m going to use this single thread as a place for you to report any sync issues. I’ll move the post over to Archived Synchronization Issues after I start a sync for your account. That thread will act as a catch-all of all the sync issues we’ve ever had to work through.
I may not reply to your note here - I may start a sync for your account and move your note over to the archive thread. Let me know if you’re re-reporting an issue so I can pay closer attention to it. 
Strava users: It may help things along if you log out of CityStrides and then log back in. Please be sure to leave the ‘View data about your private activities’ checkbox checked in Strava’s login page. Logging out/in won’t fix the issue for old activities, but it should make it so new activities are synced over.
EVERYONE: Do not de-authorize/revoke CityStrides from having access to your activity tracking service. Doing so deletes all of your data here. Only de-authorize/revoke if you want to leave CityStrides.
Activities with missing maps: Delete the Activity (while viewing it, there should be a Delete Activity [ID] entry in the menu) and the next sync should bring it back in correctly. If you have too many of these, let me know - I’ve got a script that’ll do the whole process in seconds.
April 2019 Update
In early April, I moved my database. The whole process took way longer than expected, and nothing synchronized into CityStrides during the migration. I’m very far along in getting that backlog into CityStrides, but I’m not completely finished. Let me know here if you’re missing anything from early April. 