OLED Tv will not power on.

Greetings,

We have an OLED65C9PLA that's 18 months old (to us) bought new. It will no longer power on. The Standby status led is on, and will blink off when power button pressed either locally on panel, or via smart remote, but the panel never lights up, and the standby LED comes back on. This will only happen 3x. After the third time, the standby led remains on, regardless if power button is pressed on the tv, or via remote. I've replace power board, t-con, and mainboard supplied by an online repair site, and the tv still does the same thing. Any ideas? Any direction? Should I just blow this piecer up and get a new one? Thanks for any and all input!