error in validation service

hello,

i have one validation code which creates membership plans. This validation code is running personally but when i am running it using mashup it shows an error "unable to parse json request", when i clicked on Add button mashup is shows error, how i solve this error ?

below is the mashup view snapshot which helps you for better understanding:-

below is the validation code:-

var Priceresult = me.validateInteger({
number: Price /* STRING */
});

// result: INFOTABLE dataShape: ""
var result = me.checkPlanName({
plan_name: plan_name /* STRING */
});

if(result.length > 0){
result = 'Plan Name is already exists';
}
else if(plan_name == "" || plan_name == null){
result = 'Please enter Plan Name';
}
else if(Price == "" || Price == null){
result = 'Please enter Price';
}
else if(Priceresult == false){
result = 'Please enter price in number';
}

else if(plan_type_id == "" || plan_type_id == null){
result = 'Please select plan type';
}
else if(plan_type_id == 1){
result= '';
}
else if(plan_type_id == 2){
if(MembershipLength == '' || MembershipLength == null){
result = 'Please enter number of days';
}
else if(Dropdown == "" || Dropdown == null){
result = 'Please select membership length';
}
else{
result= '';
}
}

else if(plan_type_id == 3){

if(FromDate == '' || FromDate == null){
result = 'Please select From date';
}
else if(ToDate == "" || ToDate == null){
result = 'Please select To date';
}
else{
result= '';
}
}