What's wrong? 怎么了？

I can't hear clearly. Now there's no answer at all. 电话听不清楚。现在完全没回声了。 

The connection was bad.  通话情况很糟。

The connection was bad. 通话情况很糟。

Yes, there was a lot of echo and I couldn't hear clearly. 是的，回音太多，我听不清楚。