Simplified Chinese word doc to C5 gets converted automatically to traditional

A client of mine has few word documents in Simplified Chinese.
When we copy a document to C5 editor, it gets converted to traditional Chinese automatically.

any reason for that?

We have done different ways to keep the simplified font, but when we do these things, we lose the word formatting.

So the goal is to copy the word document in Simplified Chinese, maintain the word format and copy it to C5.

can anyone help?