The Enfield Haunting (2015)

S2E16 A Fine Mess

Following a glitch with the usual materialization system, Odd and Yumi find themselves swapped into each other's bodies. To make matters worse, their atoms begin to break down due to the dematerialization, affecting them even while on Lyoko. The group must rush to Lyoko to resolve the crisis before Odd and Yumi face permanent disintegration. However, their mission becomes complicated as Xana intervenes, determined to thwart their efforts.