Line Break in Bootstrap 4.3.1

I’m trying to insert a line break between elements within a column (col-6) in Bootstrap 4.3.1, I’ve tried things like ‘
’, whitespace, clearfix, row-column-row-column, w-100, col-12, pseudoelement, but nothing seems to be working, I just can’t separate one thing from the other, and everything is shown in the same line, any advice…?

Do you have a snippet of the relevant code to show?

I’m trying to separate “Available colors”, from the color circles, that should be in the line below:
https://jsfiddle.net/Douchepool/m4cofad9/2

Adding flex-column after d-flex worked for me.

<div class="col-6 d-flex flex-column justify-content-center align-items-center">