You could use the advanced tab to change the color scheme.
this is a demo for mx8, but it's nice to test things with https://mydemoversion8-sandbox.mxapps.io/p/charts
change the data tab to:
[
{
"hoverinfo": "none",
"type": "pie",
"sort": false,
"values": [
19,
26,
55
],
"labels": [
"Residential",
"Non-Residential",
"Utility"
],
"marker": {
"colors": [
"red",
"yellow",
"green"
]
}
}
]