Mars Scientist interview questions

I applied online at the beginning of April, HR contacted me at the end of May to set up a phone screen. The phone interview went really well, HR stated that they were interested and I was a top candidate. Even said hiring manger was interested and excited to meet me. Said we would be in contact in a week to set up an in person interview. It is now the end of June (a month after the phone interview) and I have yet to hear back regarding my in person interview or anything. I even reached out to HR to ask for an application status update and received no response. My application status online now says "requisition closed" instead of "under consideration" like it did during my interview process. Extremely unprofessional that they could not get back to me and tell me they had chosen another candidate, or anything along those lines. Why seem interested during the phone screen, then completely fall off the face of the earth?