Lightning Rod Fail?

[Vietflame]

So I was doing super doubles at the battle maison running with my Sceptile and I went up against an Electross. I mega evolved and went for a swords dance, the Elektross went for a T-Wave and it effected me. I was a little confused but I kept going. The next turn, it went for thunderbolt and it did damage to me. I was like "wth?" so I looked at my ability mid battle to make sure I was "ok." Surely enough, Mega Sceptile's ability is Lightning Rod? Any idea what happened?

[ChaseInfinity]

The only think I can think off is that sometime In the battle eelektross used gastro acid nullifying your ability cause I know he doesn't get mold breaker and unless the other pokemon did something that's the only thing I can think off

[Vietflame]

Appreciate the help! I kept going and lightning rod worked properly! Yep I must have missed the gastro acid! Thank you