Non payment for Survey

I'm a member of Springvale online and have completed a survey and received an email in acknowledgement of my pending payment in this case being Airtime the promised date was the 20th August.When it was the beginning of September I sent them 2 email through their website but no one got back to me,but the survey emails keep coming how am I expected to complete them when they fail to pay their members?!I really thought they are professional.