Sorry, I didn’t catch you.对不起，我听不懂你说的。

Sorry, I didn’t get what you said. 对不起，我没听懂你说的话。

Sorry, I didn’t understand. 抱歉，我听不懂。

I can’t hear you very well. 我听不太清楚。

I can barely hear you. 我几乎听不到你说的。

I’m having trouble hearing you. 我听不清楚。

We have a bad connection. 通讯效果不太好。

I can’t catch what you are saying. 我听不太清楚你说的话