Mersive Senior Software Research Engineer interview questions

Two short phone screens, followed by a remote final-round with several people. Initial phone screens consisted of general questions about work background, academic interests and technical skills. Phone screen consisted of five rounds covering machine learning knowledge, software engineering knowledge, and product reasoning. Was contacted after interview and told an offer would be given within days. Then they said they weren't hiring for my skill set and ghosted me. Highly unprofessional; would not recommend.