SingleStore Software Engineer, Backend Intern interview questions

I went to 3 technical interviews. In the first one I was presented with a code base and was asked to add a simple functionality within an hour. The second and third interviews were algorithm based. Afterwards I was told to wait for an email regarding a normal interview and that email never came. I contacted the HR individual that approached and then and only then was told that I was not a good match for the company. Some very poor communication on their end.