Vinir Engineering interview questions

HR round followed by Interview by COO Interview scheduled at unit 1 but later at the end moment they asked me to go to unit 2 which is 20KM away for HR interview and later for another round I was asked to go to unit 3 which is 20 KM from unit 2. Initially they have asked my expectation on salary, I asked for 20% on current salary and HR asked me for interview and later after all the rounds, they have given offer with 10% less than the current salary.