For two years our ice maker got progressively worse, until it could barely put out a few lumps before it would completely ice up and stop. We were constantly defrosting it, it would go a day or two, then no ice.
There are two solutions that you can find in youtube videos.One is a pair of Y clips that fit over the freezing coil to redirect condensation. The other is this ice maker assembly. I found the Y clips for about £10, and this ice maker for around £110 and decided to do both jobs at the same time as you need to remove the ice maker assembly anyway to fit the Y clips.
After a nervous few hours of no action, it started producing ice. It is now three weeks later and it is filling the tub with ice all the time, with no ice build up on the unit.Absolutely brilliant, highly recommend.