Tales of Xillia's combat is hard to navigate..

[Kresnik]

Soriku said:

If you're jumping, you're pressing up on the stick. Try not to do that lol. I was actually having trouble getting the jump to work at the beginning, though that stopped being an issue after a while.

Also play Jude.

It's just... movement is relative to where you start on the battlefield and you have to move the stick in the direction of the enemies to move towards them.  A lot of the time, that involes pressing up left or up right, and then the character will just jump.  It's frustrating, but happening less frequently now.

And possibly I'll give Jude a try, but Alvin is the man.  And I like having Jude as a link partner to pick me up when I get hit, which happens a lot.