Azirs ulti not knocking back on contact with enemy champions

In my most recent match as azir i had around 5 situations where i attempted to ulti a rengar of jax mid jump or just after they landed and the ulti passed thought them no damage was dealt they did not have Banchee's veil or a morgana on their team. This bug frustrated me as i lost 5 good teamfights for it.

1. Exclamation claiming rengar is in ulti appears above head
2. Rengar jumps on azir
3. Azir used his ulti to knock rengar back
4. Ulti fires as it normally would but ignores rengar and does not deal damage Situation 2
5. Jax is chasing azir
6. Jax is catching up and reaches azirs ulti range
7. Azir ultis jax to gain some distance
8. Ulti fires as it normally would but ignore jax and does not deal damage

To recap i believe this needs to be fixed as azir has a high skill kit to begin with but without his ulti he is just assassin chow and with this but you cannot hope to carry i sadly do not have a screenshot or video as my computer can handle side programs but it is the most recent match in my match history if that helps.