trynd dying during ult from something AP related [GAMEPLAY]

I'm repeatedly dying during trynd ult, 1-2 seconds in at max rank, enemy team is Zed, Yi, Vel Koz, Azir, Varus, it does not happen vs the Zed, Yi, or Varus. I feel like it is the new Liandry's that is bugged, but other ap items they have include deathcap and morellonomicon, void staff and luden's echo. This happened around 7 times, and only when I ulted when the two AP champions were around, never during fights with just their AD.