On Mar 31, 4:02*pm, Mrs P wrote:
I planted a screen of 25 Fargesia nitida two years ago. They flowered
last autumn and now look as though they're dead. The supplier doesn't
appear to be interested in replacing them and has suggested that they
may improve when the weather warms up. I appreciate comments please.
Thanks.

--
Mrs P

Plant something else, bamboo does flower and die occassionally during
the natural life cycle.
You might get some regrowth, might not.
If I was a grower I wouldn't feel any obligation to replace them
either.
Did you collect any viable seed?