Lumentum Operations Mechanical Design/Simulation interview questions

Was asked for an interview which was a fairly normal 45min interview with mostly behavioral questions and 3-4 technical questions. I was told I’d hear back within a week. Two weeks later, I was contacted and asked if I was still interested in the position. After accepting and attempting to call for more information, I was repeatedly rescheduled and then ghosted for a month (after sending follow-up emails three times). After emailing them once more letting them know I had a competing offer on the table, they finally replied and said the internship has been filled and to contact them again in the future. Suffice to say, I will never be looking to work for Lumentum in the future after how unprofessional and careless they’ve conducted this interview process.