If youre images are rotated on your website unexpectedly, it could be due to hidden EXIF data stored on the image when taking the photo
To remove EXIF data from your photo
Once you have uploaded the image, in the image editor, you can use the "remove metadata" tool on the left hand side of the photo editor.
Once done your image may need rotating again, but it should now display properly across different devices.
Or: you can visit a 3rd party website such as http://www.verexif.com/en/
There will be an option to remove exif data and download a cleaned image.
Once done your image may need rotating again, but once done should display ok across different devices.