I’ve had this problem. Start by making sure your seat sits all the way to the left (seated on the bike), when latched. Is it level? Sometimes “straightening” the brackets will get the right side a bit higher, so it clears the shock when opened. In one case, I did make a pair of shims to go between the seat and the brackets (1/8” Alloy). My K1 frustrated me on this a few years ago when I stumbled on a brand new Honda seat, in the box. It looks fantastic, but totally fouls on the shock top. I’m careful, and remove it when working on the bike!