0👍
That’s because your canvas
element is not loaded yet, wrap your main.js
code in DOMContentLoaded
callback function
document.addEventListener('DOMContentLoaded', function(){
// wrap your js code here
}, false);
// with jQuery
$(document).ready(function(){ /* ... */ });
// shorter
$(function(){ /* ... */ });
Update
Also check your js code
let ctx = document.getElementById('pie-chart').getContext('2d');
let chart1 = new Chart(ctx, config);
Source:stackexchange.com