HSS25IFMDWW- freezer frosting up but working (by 3 users)

Our freezer is frosting up and gets warm at the top of Frig and Freezer but everything below the icemaker is fine. Also when the top (above the icemaker) gets warm the fan will not come on when closed but everything below the icemaker stays cold. During this time the ice in the ice compartment starts melting. After a few days the ice starts freezing again in the icemaker and everything seems back to normal for about 5 days. Then we start all over again. Any help would be greatly appreciated.