Error: read ECONNRESET when use quite big css file and many attempts in same time

[MuhamadIsmuaji]

Hi maintainers, this is the log for the error

as information for the external css file, I use Bootstrap CSS. I use code that similar with written in docs

InlineCss(htmlEmail, options).then((html) => {
  console.log(html)
}).catch((error) => {
  console.warn("INLINE STYLES ERROR");
  console.warn(error);
});

The error always comes when many attempts in same time. But when I remove that refer to Bootstrap CSS file, the error disappears with same case.
Is anyone ever face the same issue? Also, Is it true the issue is caused by use of css files that are quite big?

Thanks guys