Upload file fail since size over the limit, but it's not

Questions and Answers
1

I add sizeLimit to plugin as 500kb just like below:

  upload: {
    config: {
      breakpoints: {
        xxlarge: 2000,
        xlarge: 1500,
        large: 1000,
        medium: 750,
        small: 500,
      },
      sizeLimit: 500 * 1024
    },
  },

it works on my localhost.
But it’s wired when I upload a file about 420kb size and it’s failed, and also upload a file about 460kb but it’s worked.

Any help very much appreciated!