I am not a fridge repair person. Just some physics and how things work person.
https://www.google.com/search?q=how+to+fix+your+deicer+in+your+refrigerator finds prior discussions and videos. My bet is it's a bad connection or failed deicer unit.
MODEL: RB1855SW
So, months ago I started noticing that the fridge is getting warm. It got to the point that it was at 15C, so I opened up the back of the inside of the fridge, and the metal "coil" is full of ice. I unplugged the fridge, used a hair dryer to get the ice off (lots of ice), dried it, and plugged it back in. Sure enough, the fridge was back to normal, and it stayed that way for a full 2 weeks.
After this, it starts getting warm again, first a couple degrees in a day, then really quickly.
I called a tech and he came three times, replaced the temp sensor, but that's it, he couldn't figure it out.
So now I'm defrosting the back metal plate every 2 weeks.
Could it be the temp sensor and the second one I got is also bad? The only other thing I saw that is probable is the evaporator fan?
Any help would be hugely appreciated.
The freezer is always fine, at -18C and doesn't fluctuate. I keep the fridge at 4C but like I said, this goes up quite a bit after the back freezes over.
Thank you in advance, I'll try anything.

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