LADY REDS ZJ

SO last Friday I backed out of my driveway and followed my wife to her work for coffee. Like I do every morning. I left her job to go to my place of work and again I backed out of my parking spot. After 8 hours of being at work I put our 98 zj into reverse and it would not move. no loud noises no grinding nothing. It goes into all other gears and drives fine. I have heard its a bad transmission a bad reverse band clogged lines blocked reverse oil port. been told its a snap ring a band adjustment. and that I need a new transmission. Anyone have an answer or a possible solution. Does it need a new transmission or is there a fix