Welcome back to the world of horses!
Lunging can be tricky because horses aren't the only ones that can have a better side! I would shorten his line or put him back on a lead rope and work on getting him moving forward off your positioning, lunge whip aimed at his hips/legs or tapped on his behind lightly, and lots of verbal cues. Because the line is so long the horses have to rely on visual and verbal cues to know what you expect them to do so be clear with your body and voice. Cluck and tap with whip, staying well behind his shoulder, or even further back if need-be. If he turns toward you, keep walking toward his hip. Sometimes you need alot of room for this because the horse may want to just follow you around, turning toward you. Sometimes I'll have to tap on the shoulder to get the shoulder to move away before I can expect them to go forward and around me.
If that doesn't work then go right back to getting him to move his hip and or shoulder away by pressure from your hand - using a clucking noise or whatever as his cue. I see alot of people lifting their rein hand way up high and in front of the horse when they lunge - especially if the horse isn't cooperating. Try not to do that - a waving hand/arm can mean stop or confusion to the horse, as well.