How to make Font Awesome icons larger in my CSS?

I'm trying to make Font Awesome icons bigger using font-size: 45px; but it doesn't seem to work on my website. Here's the relevant CSS and a comparison with a working example:

My CSS:

{
    padding: 0;
    margin: 0;
    box-sizing: border-box;
    font-family: 'poppins', sans-serif;
}
.topbar{
    position: fixed;
    background: #fff;
    box-shadow: 0 4px 8px 0 rgba(0, 0, 0, 0.08);
    width: 100%;
    height: 60px;
    padding: 0 20px;
    display: grid;
    grid-template-columns: 2fr 10fr 0.4fr 1fr;
    align-items: center;
    z-index: 1;
}
.logo h2{
    color: #d34d4d;
}

.search{
    position: relative;
    width: 60%;
    justify-self: center;
}

.search input{
    width: 100%;
    height: 40px;
    padding: 0 40px;
    font-size: 16px;
    outline: none;
    border: none;
    border-radius: 10px;
    background: #f5f5f5;
}

.search >label {
    position: absolute;
    right: 15px;
    top: 50%;
    transform: translateY(-50%);
}

.user{
    position: relative;
    width: 50px;
    height: 50px;
}
.user img{
    position: absolute;
    top: 0;
    left: 0;
    height: 100%;
    width: 100%;
    object-fit: cover;
}

/* sidebar starts here */

.sidebar{
    position: fixed;
    top: 60px;
    width: 260px;
    height: calc(100% - 60px);
    background: #e26666;
    overflow-x: hidden;
}

.sidebar ul {
    margin-top: 20px;
}

.sidebar ul li{
    width: 100%;
    list-style: none;

}

.sidebar ul li a {
    width: 100%;
    text-decoration: none;
    color: rgb(255, 255, 255);
    height: 60px;
    display: flex;
    padding-left: 30px;
    justify-content: flex-start;
    align-items: center
  }

.sidebar ul li a i {
    min-width: 60px;
    font-size: 24px;
    text-align: center;
    align-self: flex-start;
}
.sidebar ul li a svg{
    margin-right: 15px;
    width: 25px !important;
}

/* main section starts here*/
.main {
    position: absolute;
    top: 60px;
    width: calc(100% - 260px);
    left: 260px;
    min-height: calc(100vh - 60px);
    background: #f3f3f3;
}
.cards{
    width: 100%;
    padding: 35px 20px;
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    grid-gap: 20px;
}
.cards .card{
    padding: 20px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    background: #fff;
    border-radius: 10px;
    box-shadow: 0 7px 25px 0 rgb(0, 0, 0, 0.08);
}
.number{
    font-size: 35px;
    font-weight: 500;
    color: #e26666;
}

.card-name{
    color: #888;
    font-weight: 600;
}
.icon-box i {
    font-size: 45px;
    color: #e26666;
}

Screenshots:

Working Example (icons resizing):

My Website (icons not resizing):

Can anyone help me figure out why my icons aren't responding to font-size?

change your style like this:

.icon-box svg,
.icon-box i {
    font-size: 45px;
    color: #e26666;
}