If you had to use Left(11) to get the full date, there's probably an extra character in there that isn't showing, because the date itself only takes ten characters - four for the year, two for the month, two for the day, and two for the dashes. You should be getting the date with the T after it if you use 11. Try isolating that problem character and adjust the formula as required to get rid of it or work around it.
