My experience with Surveys are bad, what am I doing wrong?

I'm a 19yo at Uni who is struggling to find a job here in Aus. In the mean time I decided to take up Surveys (Swagbucks) to earn a little bit of cash. The problem is, every time I take a survey I get about half way through and get denied for the Survey. Doing this for a few hours now and have not made a single cent due to this happening.

What am I doing wrong? What are some good survey sites?

Cheers