"Execute R code gives missing data for date values"

I have the following code in R Studio:



This gives the following results:

I have put the code in Execute R which is as follows:


This gives the following results set:



The dates have missing values?
Is it something to do with date formats in R and Rapid Miner?  Please assist.

My XML code is as follows:


<?xml version="1.0" encoding="UTF-8"?>