TaskRabbit Senior Full Stack Engineer interview questions

This has to be the most incompetent interviewing process I've ever seen. I was moved through a couple of rounds and then asked availability for the next round. After submitting my availability I was assigned an interview time not within my requested times. I sent several emails trying to reschedule and never received a response. Months later I've already accepted another offer and I'm still getting various emails from them about moving to the next stage despite not having any interaction. This is highly wasteful of candidates time and makes it difficult to take this company seriously.