You might be jelqing too fast and/or too soft. Jelq strokes are supposed to last 3 seconds and you might have to grip your penis pretty hard to get the most out of a jelq stroke. It also helps to do dry jelqs instead of wet jelqs, as they’re a bit tougher to do and you can really feel it when doing a stroke (I only wet jelq when my penis gets really dry). Also, I think counting jelq strokes instead of just jelqing until time runs out gives you a full workout. Since I do 400 jelq strokes a session, I count them. Sometimes I can finish it as short as 35 minutes. In other sessions, it took me nearly an hour to finish (I get interrupted way too frequently). I remember when I did quick jelq strokes. I saw no results for it and I did it for a pretty lengthy period of time. After I did slower jelqs over 3 weeks, I at least saw a more prominent vein, so it does work. You might not be doing it right.
I’d say don’t give up on jelqing. Just change around what you’re doing, because something isn’t obviously working.