• Install "Check Duplicate Values Inside List" Component to service studio
• Client action "CheckDuplicateValues" accepts JSON data as input parameter and it returns duplicate value with the help of JavaScript.
• JSON should be in the simple format. Ex:

[{"Country":"India",

"State":"Mumbai"

},

{"Country":"USA",

"State":"New York"

},

{"Country":"India",

"State":"Gujrat"

}]

• Currently it will not work for nested JSON. Ex: 

[  {
"country": {
"Code": "",
"Name": "",
"DisplayName": "",
"Description": ""
},
"state": [
{
"Code": "",
"Name": "",
"DisplayName": "",
"Description": ""
      }]