Nami bubble not properly applying cc?

I have been playing Nami for a decent amount of time, she is also probably my favorite support. One thing that I have noticed recently, however, is that there will be moments where a target within her bubble's area of effect are not knocked up or damaged. I have found that this bug occurs most frequently when the enemy champion is next to or up against terrain. Two spots that stood out in particular are the wall from mid lane towards either side of the river, and the wall just north of blue buff, the one not directly next to the tier 2 turret.

   The best example i have of this occurring was when I tried to bubble a Braum that was directly up against the point of the wall north of Blue buff, the one on red side, and the bubble landed exactly on top of him. He was directly in the center of the area of effect, but he was neither damaged nor knocked up! He did not use any of his abilities to block or dodge the bubble either. I do not know how a point blank, well centered bubble does nothing. He had no spell shield items either, and his team was not nearby.

   Is anyone else experiencing this issue? Are there other champions that are experiencing this type of issue? (Also, none of this involves the bugs with the DJ Sona skin causing skill shots to miss.)