I have maytag refrigerator(mbb2254) refrigerator or bottom roll out freezer is not cooling at all.

What is the temp in the top part?

Not sure exactly, but warm now and freezer the same no cooling now at all.

Could be the compressor, cooling fan or low Freon. Can you hear the compressor or fan running? Depending on age, may or may not be worth repair.

Unless this unit is fairly new, less than 8 years old, I probably would not try o repair it. Most repairs have to be professionally done so is it worth $200-$300 to fix this unit.

I would not necessarily give up on fixing it. It would be extremely rare for it to be low on refrigerant. That used to happen on old type units when someone used an ice pick to remove the ice. Now it's a very serious problem if it ever happens requiring welding up a leak. More than likely it's dirty or you have a bad condenser fan; of course, if you failed to clean it you could have burned up the compressor which is never covered by most warranties if you failed to do something like clean it twice a year.