[SSJup81]

Hi there. I'm in need of a translation pretty quickly, so thanks in advanced to anyone who can help me with this.

I was working on my Japanese homework, and I, for the life of me, can't figure out how to say, "I lost my voice." I know how I can say, "I couldn't sing"...Watashi wa utauttaindeshita. (I think that's how I'd write it)

*We're using nda and ndesu in class now, so I'm trying to incorporate it*

How would I say "Last week, I was sick and I lost my voice."

Would it be....

Senshu, watashi wa byooki ga dattanda kara hanasu koto ga dekinakattanda.

I personally think this is wrong, though, so any help will be highly appreciated.