When i Generate Live Load the spacing between truck axles is 6.0 m not 1.8 m , i suppose that this is a pug in software which see 6 otherwise feet or meters. how can i violate this problem?
Its not mentioned in your question whether you are working on Leap Bridge Enterprise or RM Bridge .
I checked Leap Bridge program and in the Live load Library there is Metric Design truck, Tandem and Lane option available.
In these options the distance between the axles are shown 1.8m .
So in the Loads TAB instead of selecting Design truck Select "Metric Design Truck, Lane and Tandem for Analysis and Design Purpose" , This resolve your issue.
Please let me know if you need any additional information.
Please see the attached screenshot for more information.