Ok so i ranked up from plat 1 to plat 3 yesterday by winning 7 games in a row and today i won one and queued again and it was full diamonds and their last ranks were immortal and as soon as i saw their act rank i shat myself and yeah played...

It's been broken since Yoru's release, I believe. When you scroll to change page on the wheel, you change weapon too. I'm surprised it hasn't already been fixed.