Without using/opening a copy of your character I would guess that the arm part is rotated to another angle thus showing a different sprite.
In Composer Mode, to check that the sprite is in the correct position, select the body part then open the Sprite editor and click on the Full Angles button. This will show the sprites for each angle for just that body part.
76% of original size (was 660x19) - Click to enlarge
To check if the right sprite is showing in Stage Mode, select your character, rotate to position, then open the Runtime Composer.
Select the body part from the Runtime Composer character model and check that the angle showing matches the characters rotation angle and that the sprite showing is correct.

If the correct sprite is NOT showing, then use the 3D Motion Editor to rotate the arm to the correct position as I showed previously.
Jeff
Get my Plugin Manager and TaskNotes plugins for iClone.
Check out EZColors and Other products for CTA/CA. EZColors: the easy way to change Render Styled (RS) colors!
See my CTA Tutorials on the YouTube channel CTAStepByStep