There were three rounds in total: two technical rounds followed by one HR round. In my case, an additional technical discussion was conducted to gain further clarity, but they did not get clarity even in the third round. Interviewers try to cover everything and look for a perfect candidate. You should be able to answer 100% of their questions; otherwise, they may be confused about whether they should hire you or not.
The first, second, and third rounds covered similar topics, with increasing depth and different levels of technical discussion across interviewers.