5 or so year life span designs in short. You'll find sets by other makers with your same complaint (similar post like yours, just change the make.)
So that has folk swearing off maker after maker. My reaction to this was to not buy the maker's most expensive models. Also I don't give them a nickel for "Smart TV."
The problem of repair is CTR (cost to repair) along with MTTR (mean time to repair) can approach half of a new set. And that's if you can get a shop to look at your dead TV.
https://www.cnet.com/products/lg-60la6200/review/ wasn't that compelling so your next set might outshine this one.
CNET has a lot of guides on TVs. Here's one.
Want to DIY (do it yourself) repair? Start here:
Turned my 4 1/2 year old TV on today and get the LG splash screen for about 45 seconds with a normal screen "back lights" then it goes completely black and wont do anything. I pulled it off the wall and you can see the LED's are on through the vent slots, till the screen goes black. Is this a common problem with LG TV's and is it worth fixing? TV worked great until this point. I thought I had made a great buy then I bought this TV loved the TV but for the price and not even getting 5 years use out of it I'm second guessing buying a LG product.