I've been having these question-mark problems for years. Garmin Connect app names my activities with these characters and the web site is littered with them all over.
Previously Garmin Connect named my activities in Russian... I guess it decided that because I live in eastern Europe I must be speaking Russian. Afterwards it has been messing up the encoding completely and now it's just those question marks.
I'm not really expecting Garmin to correct it any time soon. I'm just exporting all my activities to Strava and never look at them on Garmin site.
Actually... now that I was looking at the problem again I noticed that on my settings page my language preference was set to العربية (Google translate says it's Arabic). Perhaps it's selected by default because it's the first option in the list.
However, nothing changed after switching it to English. Still question marks everywhere.
