9 Count interview questions

I was emailed the day after I submitted my application for the Chief Operating Officer inviting me to an initial video interview call. At the end of our initial interview she told me that she wanted to advance me and wanted me to come into the office for a 2.5 hour interview with two specific people, in addition to herself as she would be in town, early the following week. I emailed her my availability and never heard back. I followed up a week later and still... no response. Incredibly unprofessional. Ghosting candidates is NEVER acceptable.