Rotatin actor uses wrong angles

I’ve setup a system so that when I click on an actor, it flip 180 degrees about the Pitch, but once it reaches 90 degrees it instantly flips its Roll and Yaw 180 degrees, then continues and end up in the initial position. It’s only supposed to flip about the Pitch.

Visual explanation:

Blueprint pt.1
Blueprint pt.2

The ‘∆ Rotation’ is just a float track going from 0 til 180 during 1 sec.

(I couldn’t figure out how to scale the pictures once uploaded here, hence why i use DB links)