Remove Vertical Spacing Between Divs - ASP.NET & Bootstrap

Question

I'm having trouble figuring out whats causing the extra gap between my divs that I am trying to use as cards. I want the columns of the 2 buttons to be more closer together. After finding some similar posts on SO, I tried removing the padding and looked up gutters as well in Bootstrap to see if that could fix the issue but I'm still having problems. Is there something else I should be using instead?

Here what the UI currently looks like, I'm trying to reduce the space in between the cards.

 <div class="col-md-3 padding-0 no-gutters">                    
                    <a href="First.aspx" class="btn dashMenuButton"><i class=" align-middle fas fas fa-users fa-3x"></i><br /><br />Card 1</a>
                    <a href="Second.aspx" class="btn dashMenuButton"><i class="fas fa-users-cog fa-3x"></i><br /><br />Card 2</a>
             </div>
             <div class="col-md-3">
                       <a href="Third.aspx" class="btn dashMenuButton"><i class="fas fa-building fa-3x"></i><br /><br />Card 3</a>
                       <a href="Fourth.aspx" class="btn dashMenuButton"><i class="fas fa-user-tag fa-3x"></i><br /><br />Card 4</a>
                </div>