Microsoft Senior Machine Learning Engineer interview questions

Applied through referral. Within a week I got an email from a hiring manager to set up the first interview. It includes 1 LC medium and 30' talking about background and previous project. After passing this round, an internal recruiter reached out to set up the onsite. This recruiter is the worst I have ever worked with. Very unprofessional, non responsive, didnt confirm with me the time until the last minute, with no additional information. They did not confirm the time until the day before and I kept sending email to try to confirm. I was kept in the dark also on what's coming (so yeah I have no idea what should I prepare for this interview). I was inexperienced and a pushover for not delaying the interview because of lack of information. Onsite had 4 rounds: 1 LC hard (linked list), 1 data structure (create a database to store data efficiently), 1 system design and 1 general with a PM (ask me to compare Microsoft and Google product and recommend one). Nail the LC, but average on the other 3. And never got any feedback from that recruiter except a rejection after 2 months.