ACS Style Superscript


I need some help. I am using Endnote X7. I need to use the ACS style,superscript. This is the requirement: when citing more than one reference at one place by number in one of the numerical systems, list the numbers in ascending order and separate them by commas (without spaces as superscripts).

When I select ACS style, I get the citation numbered in ascending order separated by comma but (with spaces as superscripts). 

How can I remove the spaces?