Can you post the model number please.
Ok what you will find is the panel inside the freezer at the back were the fan is will be blocked with ice. Ive come across this loads of times on these its quite a common fault as the noise will be the fan hitting the ice.
What you need to do is empty the freezer and from there remove the back panel by undoing the screws there.
Then you can remove the back panel and disconnect the wiring to the fan motor.
Then remove the fan motor from the plastic panel and melt all the ice in there.
But if you don't want to go removing panels then you need to empty the freezer and turn it off for 24 hours and keep the freezer door open. This will allow the ice in there to melt away and cure the fault.
Then turn it back on and you will find it will be back to normal from there. Ive seen this loads of times and its always ice blocking in the fan motor.
Please .forgive my ignorance but you mention the panel inside of the freezer being iced up. .. The freezer part of my refrigerator is OK it is just the top half,( that I call the fridge) that is not working otherwise your explaination is quite feasible. I am sure my nephew will locate the panel that you mention and follow your easy instructions.
That's right its the freezer you need to check.
As this appliance is frost free basically the fridge section is an empty box. All the cooling is done in the freezer and the fan in there blows the cold air into the fridge section.
So when you get a fault like this were the fridge isn't cold but the freezer is the fault is always inside the freezer section.