Little Black Book interview questions

I applied after which the HR called me. I was invited for 1 round of interview and was given 1 assignment. After which, I asked for feedback and then was asked if I was interested in accepting the offer

The interviewer ghosted after a few messages exchanged over whatsapp which to me seems unprofessional. I even shared my Portfolio with them and did not hear back. I was definitely overqualified for the role and wanted a salary hike from my current position which is why I'm assuming they didn't go forward with my application. But expecting a reply is basic decency.