From an absolute Pro Bass instructor I had when I was a young teen. This dude was phenomenal:
Turn your volumn down, rehearse the movement slowly R,M,I (Ring, Middle, Index fingers in that order)
Continue by shifting notes and on different strings.
Try scaler and intervalactics. Keep rehearsing the RMI.
2 finger plucking is popular, however at some point that Ring finger is going to come into play so coordinate and strengthen the appendage.
Pick up speed in a few days a few bpm's faster.
Going fireball at the get-go doesn't facilitate the muscle memory. Go for clean repetitive RMI but initially at slower RMI cycles.
Sound every note with the same dynamic and same BPM throughout. Even strokes, even time.
As your finger strength increases and the attack has more controlled focus and power your improvements will bear fruit.
When you're not rehearsing your strength and timing you can play as outlandishly as you wish, but set aside 20 minutes a day for this exercise.