Elton I have this same issue. All I can suggest is doing what I did. Watch the scale videos, and play the scales over and over like 10 minutes a day, I did it a half hour a week in one sitting. Within two months, I’ve started to notice a huge improvement with my pinky, I can play more complicated triplets now because of it.
Just watch the videos on the caged system, and listen to where he puts his fingers, and just let your pinky work it in. I’ll tell you tho, after the first session your entire wrist will kill for a week lol