Zantedeschia (#2)

In Summer of 2003 I saw this specimen of Zantedeschia in a garden center.
I bought it, but for 10 years it has never even put a normal size leaf.
If you can identify it, please mail me using the contact form at the bottom of the page.

The spathe was pink inside

In 2009 I still had 2 plants they never had more than 2 leaves.	In 2013 only one tuber remained, every year smaller. It didn't produce any leaf.