A/C controls died but fan blows constant

[redlala]

I’m wondering if anyone has had this issue. My dealership doesn’t know what to do. The truck air conditioning works perfect until it doesn’t. The fan goes to about a five or six setting. Cannot control or adjust the fan speed. You cannot adjust the vents to defrost or floor. The fan constantly blows, but it’s hot air. The dealership replaced a burnt wire under the hood and it started working. But then it quit again. A day later it started working again and worked for about three days. Then it just stopped randomly.