Now comes the how to fix the 90 degree issue.
While in your camera roll looking at whatever picture you want to post in upper right corner you will see Details and just to the Left of that three horizontal lines with 3 buttons on it. Click on that.
Once you do you will look towards the bottom and see some options along the bottom of the picture.
The Second button from the Left is a box with a couple arrows going in circles.
Click on that button.
Once you click on that button you will look to the lower left of your picture and another square with an arrow going counter clockwise pops up.
Click that box with the arrow twice. Hit Done in the lower right corner.
The picture is upside down at the moment.
Repeat the above steps again.
Click on three horizontal lines.
Click on that box with two arrows going in circles.
Again click on box to the Left with arrow going counter clockwise.
Two clicks and the picture will show correct like you just turned it 360 degrees while pausing at the 180 degree point.
Now go post the picture and it shows correct like below.
Don't ask me why this fixes it because I have no idea.
It looked fine before I posted it.
And the process above to me feels like I rotated the picture 360 degrees pausing at the 180 degree mark.
Only to wind up right back where I started,
Why does the raw picture show up turned 90 degrees?
I then rotate it 360 degrees and poof the problem is solved.
Don't know what to tell you other than this corrected the issue for me.
If you need help shoot me a message and I will help anyway I can.
It's been trial and error for me.