Nami's ult interrupts friendly Zac's slingshot [GAMEPLAY]

I dont know if its a bug with the new Deep Sea Nami skin I was using or Nami in general, but during our game today, I manged to interrupt Zacs slingshot midair several times, causing him to stop while in motion and land on the ground earlier than intended.

It happened when he released his slingshot from the ground and was flying through the air, then Nami's tidal wave would pass through him and he would stop mid flight, land and walk from there.