One of my Plant's Roots are not developing

its 5-6 days old and its not making much progress. The root has been the same length for a 2-3 days now and the leaves are just barely starting to come out. I have another plant thats healthy but i need to save this
one

Let it grow. Add B-1 to you feedings according to label.

I'm growing a Purple Humbolt that started growing without it's true leaves just the sepals and now it's looking just like my other May J's.

i got some pics
the first one is the undeveloping one

2nd one is the healthy one

Let it go ahead and live.