You also want to make sure that if you complete a survey, that you leave the page open for at least 10 minutes. Don't close it right away. What I do is check my account first to make sure the credit is there, and when it is, I then close out the survey page. Also, make sure you're not rushing through the survey and make sure you answer honestly. Every now and then, you may complete a survey, leave the page open for 10 minutes or more, and still don't see the credit in your account. My suggestion would be to just move on to another one. More times than not, you will be credited as long as you do everything correctly.