Translation:I have asked her why she was living alone.
The rule about participle agreement regarding French (and Italian) participles is not quite that simple ...and the situation is even crazier because chiedere can be used in many different ways! Think of it like this:
- Ho chiesto una birra / L'ho chiestA
- Ho chiesto tre cose / Le ho chiestE
Chiedere a qualcuno
- Ho chiesto a voi / Vi ho chiesto
- Hai chiesto a noi / Ci hai chiesto