Maintenance for the week of November 17:
• [COMPLETE] Xbox: NA and EU megaservers for maintenance – November 19, 4:00AM EST (9:00 UTC) - 12:00PM EST (17:00 UTC)
Same exact happened here just now. Can't use light attacks, heavy attacks, any skills. Only can block and roll dodge, use potion. /reloadui didn't help, and being in a battleground relogging wasn't an option.