Jari brohrich I don't believe there is any way to control the direction of data between the apps. So to troubleshoot, all I can think to suggest is checking the timezone settings for the scale (done in the Nokia app by scale location I think), MyFitnessPal, and Garmin Connect. They should all be the same. It sounds to me like one of them is off possibly causing data / timestamp confusion.
Jari It very well may be a bug... But it is strange that this is working properly for me, but not for you. One more thing I would try is to delete the weight entries from today and perhaps the last couple of days from both Garmin Connect and MyFitnessPal. Then see if your next weigh-in on your Withings scale, presumably tomorrow, propagates correctly. My thinking is that if Garmin Connect doesn't have a "yesterday's weight" to copy, then it might stop doing that.