Aegis Protective Services interview questions

Met with hiring manager, spoke about my personality and goals, And then they gave me an overview of the position and culture there. Got a call back a few days later, and was offered the job. Went back in to try on uniforms and do paperwork. Relatively smooth.

Applied to a Business Development position online and received a call that they were interested and would like to set up an interview. I called them back a short time later and left a message for the manager I received the call from. After my message was ignored I called again and left a message at the front desk and eventually emailed the manager. All of this was ignored. This came off as highly unprofessional and left myself wondering why request an interview and ignore the candidate? By the way, the position is still open to this day.