chart js chart move it self to bottom of page

in my html i have this code below

           <div class="col-12 my-5">
                <p class="text-center">title</p>
                <canvas id="buys_comp" style="min-height: 300px !important;"></canvas>
            </div>

and in my script code chart object like this:

let buy_froms = document.querySelector("#buys_comp")
    let buys_chart = new Chart(buy_froms, {
        type: 'pie',
        data: {
            labels: Object.keys(data.buy_froms) ,
            datasets: [{
                label: 'title',
                data: Object.values(data.buy_froms),
                backgroundColor: [
                    'rgb(255, 99, 132)',
                    'rgb(54, 162, 235)',
                    'rgb(255, 205, 86)',
                ],
                hoverOffset: 4,
            }]
        },
        options: {
            responsive: true,
            maintainAspectRatio: false,
        }
});

and show chart correctly but after seconds chart move to bottom of page automatically

image 1

image 2

video

i think some code have discontinuance with chart