DraftKings Software Engineer - Front End interview questions

All dev positions must pass the algorithms/coding interview, unfortunately front end as well (which was what I wanted). A recruiter reached out to me on LinkedIn, we talked, I was given "resources" to describe what the tech interview would involve but I wish she told me what specific data structures to have down because I am a front end dev and it's been years since I've worked with hashmaps. The interviewer was awesome, super nice and helpful and patient. I did not pass bc it was literally the only data structure I didn't master, otherwise the problem itself wasn't bad at all and I should have tried a different way. The recruiter is where I say it became a bad experience. I told her the news and asked if it would be possible to retake now that I understand hashmaps better, or if not, when would I be able to reapply/how many months? She did not respond. I decided to email- no response. It was a simple question. I wasted an entire week studying for nothing.