Frigidaire garage cold kit?

I have less than 1yr old Frigidaire refrigerator (model #LFHT2117LW).
I put it in my garage. The issue I have with it freezer doesn’t work, or not enough cold. Stuff in freezer were actually melted.
I went to Lowe’s where I bought it, and got a tel# to service center. I called and technician came, and recommended to install temperature control kit when he saw my refrigerator is in my garage without checking in detail.
He call me back later telling the cost will be $140 + tax.

I want to know the cost is reasonable or not.
Also, I want to know the temp control kit product # and price. I’m OK with DIY, and I believe I can install it by myself. (and save $$$ if the kit is less than $140)

Could you please help me??

Thanks,

What is the temperature in the garage?
If the garage is cold (around freezing or lower), the unit goes through a defrost cycle but because of the ambient temperature the compressor does not come on after a defrost cycle so the heat from defrost stays in the freezer and melts everything.
They do make a kit for this, see below. click on the picture for more info on it.
AP3722172

See the attachment for some additional info
Garage Kit.pdf (594.4 KB)

Thanks for your advice.
I’m living in Ohio and my garage has been very cold, especially for last few days.

I just want to confirm if the kit will fit to my refrig.
I check using “Appliance Compatibility Tool” of this site. It said “Sorry This part is not compatible”…

I do not know for sure.
It would be best to contact a parts representative.

But when I looked at the Q&A for this part one of them said the kit was compatible with a FRT2IL4FW7 unit but when I used the compatibility tool it said it was not compatible.
This unit looks like it uses the same/close to the same control console as your unit.

It could be that the compatibility tool just looks at the parts that are listed for that unit and since this is an add on kit it is not listed.