Each of the gradients you apply are non-transparent, so one of them will always lay on top of the other. You'll need to apply a fade effect using alpha values.
The look here for more detail: How to combine two css3 gradients ?
.double-gradient {
display: grid;
place-items: center;
height: 200px;
width: 200px;
background: linear-gradient(rgba(255, 255, 255, 1) 0%, rgba(251, 251, 251, 0.1) 100%), linear-gradient(90deg, #84d2ff, #8d5acd);
}
<div class="double-gradient">
Double Gradient
</div>