Aptec-Ingram Micro interview questions

There were 5 Interviews in Total, First with Hiring Manager (Easy) Second with RegionalManager (Difficult) Third with Country Manager (Easy) Fourth with HR Manager (Very Diffcult) Fifth With the MD ( Eye Wash, No questions were asked)

it seemed very organized and after 4 rounds of interviews and a presentation and getting promised of an offer letter they disappeared for 3 weeks and then send me an automated message from the system what unprofessional way to handle a candidate