Garmin Full Stack Web Developer .NET interview questions

The first interview was over the phone with HR a couple weeks after I applied online. It was all generic HR questions. I was told to expect second interview 10+ days later I got an email about doing a second interview. The second interview was online with a senior engineer and manager. It involved general questions about my experience and completing a pretty simple coding challenge About 2 weeks later I got an email saying I didn't get the job followed by a phone call saying the email was a mistake and they wanted me to come in for an in-person interview. This interview started off chatting about the company and more experience questions. Then I was asked to basically create a pretty simple website from scratch where a user could upload a file and generate an output. I struggled with the "from scratch" part