Unable to purcharse Weight limits for alt chatacter

As the title stated, I was playing a DK at first and bought all the Weight limit increase for her.
But when I jump onto my 2nd character which is an Archer, I'm unable to purcharse Weight limit for this one, although it is a One purchase per character (not family) item.

 

Is the character new? Weights are limited to one purchase per character. I'm sure you've already bought weights with this character and you've completely forgotten about it. Create a new character just for testing and see if you can purchase weights.

 

I tried creating a new character and it works perfectly fine, this problem only appears on my Archer somehow.
I'm 100% sure I never bought any weights for my Archer, you can see from the photo. If I bought all the weights, my limits should be some where around ~2000 LT, I only got ~1500. Also, this is a character bound item so there's no way I left purchased weights (if I did) somewhere else.