CluePoints Senior Python Backend Developer interview questions

I applied Cluepoints over a headhunter. They first made a short call with Human Resources and a long technical call with two of their senior engineers. Later, they sent a PoC. I implemented the PoC and they called me foron-site interview. In this interview, they mostly asked about my solution, details, missing points in my implementation etc and told me they would turn in a very short period. In first two weeks they just replied as "we will negotiate and inform you", and after four weeks they mailed the headhunter who sent me to them that "they havn't found my solutions in PoC enough senior". They even didn't reply to my mail asking about any update. This is so ridiculous :) They could just give this feedback before calling me to their office, which cost me 4 days of my holiday and a few hundred euros :)