I will try your method with the jar,. Where did you kept the jar, no, better how did you kept it, cold or warm?
Nothing fancy. I used a mason jar, the lid ring, and a piece of window screen instead of a lid. I would soak the beans overnight in the jar, leaving it on the kitchen counter. The next morning, I'd tip the jar over into the sink and let it drain out all the water. Then I would give it a good rinse or two, then set it back on the kitchen counter out of direct sunlight. 3X per day I would rinse and drain the beans in the jar. You don't want any standing water in the jar. The window screen lid allows good air flow to help dry out the seeds between rinsing. You might want to lay the jar on its side to promote max surface area and air flow. By about the 5-6 day, the sprouts were a good eating size and then I would put them into a container in the refrigerator. The sprouts should be eaten within the week, or they can go bad.