Alas, I do not know the name of the plant as it was given to me by a friend who also didn't know the name. It's a tropical that really takes off in the summer & produces big pink blooms. I've wintered it over successfully for two years but this year the leaves just started turning yellow and come off easily. I see that even some of the younger leaves are yellow. I keep it quite moist but don't think I'm over-watering it. I note a lot of dead leaf debris underneath and maybe this is holding a disease though it never did before. Pictures attached. Any ideas?