One of problems found by people who use LG G4 is the problem with their photos orientation. Some cases are reported that the photos being flipped to landscape orientation when the photo downloaded or uploaded online.
This problem is related to the way the LG G4 handles rotation. It uses Exchangeable Image File (EXIF) settings to rotate the photo and it might be about cutting down processing time.
There are some ways to overcome this problem although there is no real solution to it. You can choose one of options from these following explanations. It might help your phone back to normal or reduce the problem that occurs.
One of options you could do to overcome your photos orientation problem is by using a different camera app. You can get some others camera applications in Google Play Store by downloading and installing them into your phone.
After downloading and installing a new camera application, you can try to capture a picture and save it to your gallery. Then you can try to upload it and see the result if it still rotating or not. If it successful for your case, you can keep using that camera application so you can overcome your problem.
Other option to overcome your photos orientation problem is by using an alternative gallery application. You can do this option by saving your photos in QuickPic Gallery instead of using the default gallery on your phone. After you save it in other gallery app, please try to upload a photo from there and see the result, whether the photo uploaded is still rotating or not.
If it successful, then you can keep using that gallery application to avoid photos orientation problem in your phone. Other simple way to get the photo orientation that you need is using Windows Photo Viewer or other photo editor to rotate the photos on your computer.