Javascript replace not working (needed for Katalon Studio)

Hi Folks,
I am looking to use the attached Javascript in Katalon Studio but cannot get it to work.
When I load it into Chrome SIN= ‘1,3,2,5,5,8,0,5,7’ displays. I am expecting SIN= ‘132558057’.
Could someone take a look at my code to see where I am going wrong?

Google Chrome: Version 73.0.3683.86 (Official Build) (64-bit)

SIN.html (1.1 KB)

Okay solved my issue… See WorksSIN.html for my solution.
WorksSIN.html (733 Bytes)

Please close this ticket - thanks!