Kalista ult bug
I was playing Teemo support with a Kalista ADC and the issue is whenever she tried to ult me, her ult wouldn't launch me towards my destination. My ping and FPS were steady at this time and it repeatedly happened every time she ulted me. After I selected the destination, my spell icons changed back to normal but it continued to hold me inside the Kali ult. After the duration ended everything was fine, and I'm not sure if this bug works only with Kalista and Teemo or other combos.
tl;dr: Kali ult not launching me in desired direction and holding me in it for the entire duration.