Hi Virat,
You can save the data in a variable and then change the string by using the replaceAll function. In this case this would look something like:
replaceAll($JSONstring, ‘\’, ‘’). This will remove all \ from your string. Alternatively you can use replaceFirst.
Check this documentation for more info on string functions:
https://docs.mendix.com/refguide/string-function-calls/#13-replaceall
hope this helps!