Greyp interview questions

At first i got an interview with a nice hr lady and the hiring hardware engineer manager. After 1h of skype they got back to me with a positive feedback and asked me to do a 4h worth deliverable. I didnt hear back from recruiting untill i publicaly commented one of their linkedin posts 2 months after. They moved on with the recruiting process and they didnt spent even 1 min in emailing me with the news.