mobile phone survey -- qualify for more questions

[JohnPi]

I took the mobile phone survey, and at the end it said I qualified for more questions with an additional incentive. So I said OK and spent about a half-hour on the additional questions. But I didn't receive any additional incentive.

Has anyone else done this, and if so, have you received additional credit? If you did, how long did it take to show up?

Thanks.