Hi there,
I believe the forums are the place to report bugs according to https://us.battle.net/support/en/article/333758.
In D4 my camera was locked briefly on another character rather than my character.
This happened briefly for 1.5 seconds. So not very disturbing, but might be worth investigating.
Just after porting to the Onyx Watchtower during helltide. My character stood in the gate entrance between the waypoint and blacksmith. My character was no longer moving, but my camera locked on a player and followed another played briefly.
The camera followed the other player for about a full screen width. Afterwards the other played disappeared and the screen moved linearly back to my character.