Problem with keyframes and speed modification of a video

Hello everyone, I have a problem with Adobe Premiere Pro, I am editing a video in which I put slow motion with the pen to adjust the speed, but when I want to put an effect or simply that I want to move or enlarge the video with the effect "transformation" I can not put a key frame, if for example I put a video at 100% scale and I put a keyframe at 120% scale there will be no movement just because I put a slow motion, on the other hand when I don't modify the speed of the video, the movement is done. How can I fix this? Please help me, it's important.