Merck Submission Planning Intern interview questions

The process consisted of a 30 minute phone screen then a 30 minute call with a couple more team members asking about my resume/experience. The calls themselves went fine but what led to my negative experience is the lack of professionalism demonstrated by Merck. I heard back for a second interview 4 days after my first. Following my second interview I had not heard back after two weeks so I emailed the employee who conducted both my interviews. I got no response and finally after almost a month of waiting, I got an automated email from Workday saying I had not received an offer. I felt this experience to be unprofessional due to the lack of communication on Merck's end and a dragged on recruiting process.