1st I defrosted the freezer. 2- removed the inside panel. 3- turned the freezer back on and saw that the condenser was not defrosting ice was building up. 4- Searching through YouTube and found info that the defrost heater was not working. for Frigidaire, the heater control is in the Control/Electrical Panel. I ordered the part from AppliancePartsPros.com and removed the faulty one and whole! the freezer works great.
The tool I used was a 2" wide Putty knife