Getting Error while adding modifier in to the order ?

Here is below snippet code where found clover sdk documentation

List<ModifierGroup> modifierGroups = inventoryConnector.getModifierGroupsForItem(itemID);


//Check if any modifier is available to the item
if (modifierGroups.size() > 0){
        List<Modifier> modifiers = modifierGroups.get(0).getModifiers();
        if (modifiers.size() > 0){
                orderConnector.addLineItemModification(order.getId(),item_id, modifiers.get(0));
            }
}

orderConnector.updateOrder(order);

Getting below error :-

result = {ClientException@8438} Method threw 'com.clover.sdk.v1.ClientException' exception.

resultStatus = {ResultStatus@8463} "ResultStatus{statusCode=UNKNOWN, statusMessage=null}"

backtrace = null

cause = {ClientException@8438} "com.clover.sdk.v1.ClientException: status code: -1"

detailMessage = "status code: -1"

stackTrace = {StackTraceElement[11]@8465}

suppressedExceptions = {Collections$EmptyList@8383} size = 0

shadow$_klass_ = {Class@7346} "class com.clover.sdk.v1.ClientException"

shadow$_monitor_ = 1285321248

10 |2000

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question