I am having this same issue. No updates available. Only seeing this on John wick 1 and 2. Netflix does not present this issue. Futurama on Amazon does not present this issue. Video seems zoomed in as characterized by others on this post. Glad I'm not alone thought i was crazy! Can't change aspect ratio it's grayed out.
The problem lies with 2.4 aspect ratio movies (which the vast majority of movies are these days). You'll notice a Prime Video free movie called Khartoum with Charlton Heston is a 2.78 70mm movie and it plays fine on my Samsung Television. I started inquiring with Amazon last Saturday and they still have not fixed it, but hopefully they will soon.
Been at this for 3 days now!!! I’m glad I found this forum!!!
"There is nothing wrong with your television set. Do not attempt to adjust the picture. We are controlling transmission. If we wish to make it louder, we will bring up the volume. If we wish to make it softer, we will tune it to a whisper. We will control the horizontal. We will control the vertical. We can roll the image, make it flutter. We can change the focus to a soft blur, or sharpen it to crystal clarity. For the next hour, sit quietly, and we will control all that you see and hear. We repeat: there is nothing wrong with your television set. You are about to participate in a great adventure. You are about to experience the awe and mystery which reaches from the inner mind to... The Amazon Limit.."
I noticed the problem a few weeks back and it seemed to coincide with the TV updating firmware to 1233. The aspect ratio is messed up, with films being stretched top and bottom. I abandoned watching John Wick 2 due to the problem and persevered angrily through The House with a Clock in its Walls.
I have emailed Amazon (email@example.com and firstname.lastname@example.org) but have had no reply. No happy.
[Edited: Had a reply - advised to Update AV App, reset Smart Hub, re-register device. Nah, no thanks. I already know that won't work]
I meant the usual troubleshooting steps, for example AverageBear send an email to the email@example.com and firstname.lastname@example.org and they replied with the same suggestion: reset Smart Hub, re-register device. That doesn't work, if someone contact support now and report an aspect ratio issue with Prime Video app on a Samsung TV, it's useless demand him/her to carry out all that steps if your tech team know the problem and is trying to fix it, just say him/her that tech team is aware of the issue or at least send a memo to the support team and inform them on the current situation with this bug.
It's just my two cents.
Ps. And yet on twitter Amazon Help asks if tv and app are up-to-date.https://thttps://twitter.com/leegil_1234/status/1129712577238446081witter.com/leegil_1234/status/1129712577238446081
Amazon team, is there any ETA for resolution ? This thread is just growing with complaints. Not sure, What sort of technical team is working on this. This is too much, 8 days in issue yet we can't watch movie of our choice. None of us has signed up of this kind of service.
So, in summary, we can be quite certain that this aspect ratio issue showed up on every Samsung TV updated with the recent firmware 1033.0 (2019-04-23) on the tizen Prime Video App (Please note: not all Samsung tv model use the same software, for example MU6400 use a different firmware and seems that it has no issue).
Usual troubleshooting steps (de-register the Prime Video app, reset SmartHUB, reinstall Prime Video app, factory reset tv, unplug tv for a minute and press stand-by button for 20 seconds) don't fix the issue and almost every movie with aspect ratio of 2.39:1 is affected: images appear vertically stretched and there's no way to adjust the aspect ratio with the tv because the aspect ratio control on the menu is greyed out when Prime Video app is active (so, no workaround available). You can't delete and properly reinstall the Prime Video app on the Samsung SmartHub either, because default apps can't be deleted (good call, Samsung :( ). Oh, and you can't downgrade to a previous firmware like years ago, Samsung made it impossibile that too.
I even tried to reset apps via tv service menu: it did not fix the issue.
I called Samsung support team, one of their specialist verified via internet my tv set and he insisted that it's an Amazon problem, so I pointed out that the bug showed up just recently with their firmware update and that his answer was a bouncing of responsibility, he say that will inform their tech team on this issue but I'm very skeptical that they'll release a new firmware soon.