Fast Enterprises interview questions

I met with the recruiter at my college career fair, and they were the friendliest out of any of the companies I spoke to. We arranged to have an interview on campus the next day. The interview itself wasn't difficult and mainly behavioral. It lasted about 30 minutes and then they gave me a written logic test with some pseudocode questions on the back. It was the same test that the other reviewers mentioned, with the code question about finding the first 100 prime numbers. This test had a 30 minute time limit but it was pretty long and I didn't manage to finish it all. About a week later the company sent me an email asking about my availability for a technical phone interview they wanted to schedule with me. I promptly responded, and several days later I got a response saying they no longer wanted to interview me. I don't know how common it is for companies to do this, but it seemed unprofessional to me to schedule a second interview and then change their mind the day of.