Your watch is broken

I built a castle of time,
By drawing picture of clock.
I created the work of art,
It was not just homework. 

It is very beautiful, but
It doesn’t make sounds and work.
This is a simple painting,
My sister doesn’t know.

She looked at me and said:
“Sis, we have a problem.
It is well-composed, however,
Your watch is broken”.