Moody's interview questions

Got an invite 3 weeks after I applied. It consists of 3 rounds of interviews. First and second are technical and the last is behavioral. It was not very difficult but moderate.

It has 5 rounds of intervew, all are technical. First two rounds are coding based, very easy problem they just want to check code completeness. Third round focused on hiring manager and compensation. Fourth and fifth are for system design. After all the rounds and compensation negotiation, even agreed to their low budget, I got an rejection mail. When I asked for the reason, they don't have it and said illogical nonsense.