Hi, I need help to solve my sitting confusion. Everything works well except this problem

On the right side first two seats are ok, then it just skips one? I have same preferred sitting in 888 and in HM2. I also noticed that if I put in HM2 preferred seat on position 3 as is shown in 888, then seats are off for 2 positions. If I set it to position 5 in HM2 then this happens - look img.
Any help will be rewarded with thank you!