Coolblue interview questions

I had a meeting with HR. She said my English skills can be a problem for being hired in this position. Although I could express myself a little bit, I was having difficulty remembering some words since my native language is not English, but I think this would not be a problem for the job. I will relocate, have a work and residence permit max. in a month but they said they are looking for someone who has already located in the Netherlands. But it was more absurd when they said this position was opened by mistake; "we already hired someone else".

First step was to call with the HR person. Then had an interview with the team lead and a data scientist which I talked about one of my projects. After that they gave a case to do at home and send the answers. I failed at that step so I don't know what comes next.