"Sony vegas pro" support is not involved. If you don't receive an answer to your question here on this user to user forum, get in touch with VEGAS Support through https://www.vegascreativesoftware.info/us/support/
@Xengpao-THAOCHERCHING Some additional info is needed. Like the version of Vegas you have... Sony Vegas 13 and older versions might not have the lut fx needed to work with log clips... you may need to apply the appropriate lut to the footage before importing. Or upgrade to a Magix Vegas version which lets you load luts into the project together with the log clip.