When you submit your Fire TV app to the Amazon Appstore, the images have to go in the right place, or Amazon rejects the listing with "your app assets/images do not accurately reflect the content of your app." This is a listing/metadata issue, not a problem with the app itself — the app already passed review.
Two things fix it
Screenshots go under Fire TV Assets → Screenshots, not under Tablet assets. Amazon reviews your Fire TV app against the Fire TV screenshots, so those must be actual screenshots of the running app (home, browse, a video playing). A ready set is on your Tappla download page (apps.tappla.com), captured from your real app — use those.
Under Device Support, enable Amazon Fire TV and turn off Fire Tablet. Your Tappla app is a TV app, so it should only be listed for Fire TV. Turning Fire Tablet off removes the separate Tablet asset section entirely, so there is no wrong slot to fill.
Your app icon and background image can be your own branded artwork — only the screenshots have to show the actual app.
You do not need to change the app, the SDK, or add DRM
Tappla apps stream your feed directly, and Amazon does not require DRM for this kind of content, so that is never the reason for this rejection. Just fix the images in the listing and resubmit. If it still gets rejected after that, reply here and we will take a look.