Hi Raul,
What connections are you using for the stacking links, the VIMS or ports 51,52? x460s can be stacked in various ways.
Check 'show stacking-support' to see if the current stacking method is 'Native' or 'Alternate'.
If native, you're using the VIM ports for stacking and you can use ports 51,52 for normal data connections.
If alternate, you're using ports 51,52 for stacking which should go to ports 51,52 of other x460s to setup the stack.
For more info, see the hardware install guide as it has in depth details on stacking:
https://documentation.extremenetworks.com/extremeswitching/downloads/EXOS30_HWInstall.pdf