Naveego interview questions

The process was a coding assessment followed by a scheduled phone call. Exactly an hour before my phone interview, I received an email that canceled the interview because the position(s) was now filled. This was disappointing to me as time was invested into the assessment and preparing for the interview, but I did not even have an opportunity to have a conservation with them. On one hand, yes, I am thankful they informed me so we would not waste each other's time. However, an hour before the phone interview was very sudden and unprofessional. In addition, there was no apology in the email, which I would have been more receptive and understanding to. At the very least, please notify the candidates 24-48 hours in advance of cancellation as courtesy. If offers have been given 1 week before, do not keep handing out coding assessments and scheduling candidates that very week when there is an extremely low chance of proceeding.