VueJS nullish coalescing operator (??) error in v-calendar

I am getting “You may need an appropriate loader to handle this file type, currently no loaders are configured to process this file.” error

The full error:

error  in ./node_modules/v-calendar/dist/es/index.js

Module parse failed: Unexpected token (1889:19)
You may need an appropriate loader to handle this file type, currently no loaders are configured to process this file. See https://webpack.js.org/concepts#loaders
| const resolveEl = (target) => {
|   if (target == null)
>     return target ?? null;
|   if (document && isString_1(target))
|     return document.querySelector(target);

 @ ./src/main.js 13:0-35 15:0-65 27:12-21 29:12-25 30:30-38 31:32-42
 @ multi (webpack)-dev-server/client?http://192.168.88.134:8080&sockPath=/sockjs-node (webpack)/hot/dev-server.js ./src/main.js

My babel.config.js file

module.exports = {
  presets: ["@vue/cli-plugin-babel/preset"],
  plugins: [
    "@babel/plugin-proposal-nullish-coalescing-operator",
    "@babel/plugin-proposal-optional-chaining",
  ],
};

My vue.config.js file

module.exports = {
  transpileDependencies: ["@gtm-support/vue-gtm", "v-calendar"],
  productionSourceMap: false,
  chainWebpack: (config) => {
    if (process.env.NODE_ENV === "development") {
      config.output
        .filename("[name].[hash].js")
        .chunkFilename("[name].[hash].js")
        .end();
    }
  },

I have installed necessary plugin with this command:

npm install --save-dev @babel/plugin-proposal-nullish-coalescing-operator @babel/plugin-proposal-optional-chaining

But it is still not working.