Try converting the JSON String to an object using Import mapping (https://docs.mendix.com/refguide/import-mappings/).
By this way you can remove the backslash in the string.
Hope it helps!!!
You can use the replaceAll function to do this. For example, if your string is stored in a variable called $vData, you can use the following.
replaceAll($vData, '\\', '')
Note the double slash. This is because it’s an escape character so we need to escape it as well.
Hope this helps
Like Robert said:
Hi Eline Bijkerk, Please check microflow actions.