Sona bug issues.

I've played sona for awhile now almost over half of my gameplay is sona. Ive noticed there are some issues with her ult. Like sometimes it hits and does not damage or even stun. It's happened many times now and its kinda making me wanna play a new champion and report is so temporarily I am doing so. There was a game I just played with me as a sona and a thresh and Jinx was on the enemy team. I had ulted them and they moved around and still auto attacked and used spells like nothing hit them at all. My internet is good. Little to no issues. I'm hoping someone else had this kinda think that happened? Also I was using the DJ Sona skin all the times it happend. No other skins to really say. Both of the thresh and Jinx did not have any banshees veil so thats a no go for reasonable not working ult. Hopefully someone can understand what I'm talking about.