These work for me: 1. I'm so sorry, I didn't get that. Could you say it again more slowly? 2. Sorry again, the word after <foobar>, could you spell it for me?

These work for me: 1. I'm so sorry, I didn't get that. Could you say it again more slowly? 2. Sorry again, the word after <foobar>, could you spell it for me? 3. Okay, before I reply, let me make sure I understand: you are saying/asking "<unambiguous interpretation>"?