Hi,
on loading graph, this tooltip class is given display:none css already in my page
.canvasjs-chart-tooltip{
position: absolute;
height: auto;
box-shadow: rgba(0, 0, 0, 0.1) 1px 1px 2px 2px;
z-index: 1000;
pointer-events: none;
display: none;
border-radius: 5px;
}