Something goes wrong with EXIF data in the file when your device stores it, releases it or when it's preceded by chat. There's no settings at FCN for you to adjust which would affect this behavior.
Unless it's happening to masses of people and without knowing which device you're using, whether you have rotation lock enabled, how the photo was transferred to the device, how was it edited, which browser you're using, when it started happening, recent device or software setting changes and/or updates taken place, browser mode used, etc... ...there's no way to begin giving you any kind of answer.
Try rotating the image 90° (in the appropriate direction relative to your issue) at a time by editing it and see whether that makes a difference.
If anyone has/had a similar issue and has a solution, feel free to chime in.