The first conversation took place with the HR representative. She is still very junior and unfortunately that really shows. The whole experience felt highly unprofessional: feedback was repeatedly promised but never delivered on time, and deadlines she set herself were constantly missed. When I followed up, the deadlines were simply pushed back again.
Overall, the process came across as very unreliable and did not reflect well on the company. It all felt quite unprofessional. Ideally, HR should make candidates feel comfortable and excited about the company, but in this case, it had the opposite effect.