Samsung RF28HFEDBSR not cooling

[zakrya]

I have a Samsung RF28HFEDBSR ( 2015) that stopped cooling.

The unit itself will power up, the condenser fan and the compressor are running. I put a magnet on the right door while the left door is closed and I can hear the evaporator fan running and blowing air ( not very cold).
I run the self-diagnostic ( hold freezer+fridge keys for 8 seconds), no error code.
Next, I open the back panels, vacuum the condenser coils ( not dirty) and I have a solid ( not blinking) red light.
I cycled the temperature settings but after 3hours of running, from 63F and 71F the temperatures dropped to 59F and 61F but the inside is still warm particularly the freezer compartment. The outside body ( freezer and fridge doors) is relatively cold.
What could be the problem? I would appreciate any input on what I should next.

[Slav]

The next step in your case would be to check the frost pattern on the evaporator coil.

Remove everything from the freezer including the back wall. If the evaporator coil has a lot of frost and ice build up (take a picture), it could be a Defrost or a Drain problem.

If there is no frost at all, it could be a Sealed System problem (leak, clog, or inefficient/bad compressor). To go any further, you'll need to install gauges to check pressure inside.