Samsung UE65F6400 TV - Dark, less bright image at 1/3 height of screen

I warmly welcome. I am struggling with a problem with Samsung TV. For some time, at the height of about 1/3 of the screen, the image has become darker, less bright. Nothing extraordinary happened, there was no storm or other unexpected circumstances. One morning after turning it on, I just noticed it, and it still is today. Depending on the scenery, you can see it more or less. It does not move and is always the same width. I took pictures of the test screens and you can see it clearly. Can any of the men on the basis of the attached photos be able to suggest whether it is repairable? In the sense that it indicates damage and the only solution is to replace the matrix or maybe there is a shadow of a chance that it is some backlight or other electronics? I know it's hard to diagnose it from a distance but it's still 65 "and I got a little attached to it. I would be grateful for any suggestion.

Thank you. This is very good news. It is paraffinable at home - does the service come home and replace, or is it possible to use a higher driving school only under service conditions?
And what order of magnitude do you need to prepare for - indicative so as not to get stretched?

As for the warranty - they should replace the matrix for free, as after the warranty - look for a good RTV service in your area - an order of magnitude depends on the quality of the service.

Unfortunately, the warranty has already expired, so I asked for an approximate cost.

It depends on what service you come across, it can be PLN 150 and it can be PLN 400.

And this is concrete. Thanks for the info. If I manage to find a service that will undertake repairs (which may be difficult), I will share information.

I have more or less idea that this is how it looks like. One thing I am concerned about is that there is only one "sensible" site in my area that can do this. If it turns out that they won't want to, I'll have to look somewhere else. If, on the other hand, they take up the topic, at least thanks to you I know above what rate the lamp should light (to put it mildly). I'll call you tomorrow and try to find out. Thanks for the help. If someone started telling me that the matrix needs to be replaced, without your help I would probably be inclined to believe.

I come back to the topic after almost two years. I used to ask for help with my tv but somehow managed to survive when it came to one bar. Currently, the problem affects almost half (bottom) of the screen and it seems time to do something about it. Could any of you recommend a trusted professional from the Opolskie, Dolnośląskie or Śląskie voivodeships? I think that in a radius of 100 km I would be able to easily drive up and deliver it in one piece.
If my request would in any way violate the rules or rules prevailing on the forum (sorry in advance), please let me know on priv.
Thanks in advance for any helpful information.

Colleague "Jarzabek666", do you remember what model of LED strips in this TV? I do not have a service center for this model.

And I am a little different - I have an additional "guarantee-insurance" I reported dark spots in advance and a service technician came but "this is dust, it is normal - one does not repair" is he right?

For me it is definitely not dust