GE 20DADRWH Upright Freezer

Good Evening! Freezer has been great for years and years. Last week alarm came on. The ice cream was more like a milkshake. Unplugged, let thaw. Gave a good cleaning. Powers up. Cools down to about "zero" degrees F. but the Alrm buzzer sounds 24/7. Have to turn the alarm off. I’m having trouble identifying the part that sounds that alarm. Any Idea and or hints would be appreciated. I’m pretty handy as long as it doesn’t involve Freon. Thank you to the group. Rob WA4IPE