This worked for me perfectly in bootstrap 4.4.1 !!
.nav-pills > li > a.active{
background-color:#46b3e6 !important;
color:white !important;
}
.nav-pills > li.active > a:hover {
background-color:#46b3e6 !important;
color:white !important;
}
.nav-link-color {
color: #46b3e6;
}