SAP Internship interview questions

I got offered an interview a couple of weeks after my application, we scheduled a phone interview but I was told no more details. I emailed twice to ask for more information on the interview - would it be technical/behavioural ect. After a week ( the day before my interview) I received an email saying it was going to be cancelled because they decided they wanted a 6 month intern not a 3 month. This was never stated anywhere on the job description and I had already started preparing for my interview so lots of time was lost.