Animation scaling problem

Hello, I would really appreciate your help! I’m just starting out with Unreal Engine 5.5 and wanted to create something funny to begin with the basics. I downloaded a model from Sketchfab, then animations from Mixamo, and everything was working fine. Later, I decided to create my own animations directly in Unreal Engine. I made them using Level Sequence . During the preview, the animations look as they should. However, as soon as I replace the existing animations, my character scales up multiple times during the animation’s playback. For example, this happens when replacing the jump animation in my case. The only workaround I’ve found is to retarget the animation from this model to the same model (???) and use the additive animation type . But again, this is just a workaround, not an actual solution. I’d be very grateful for your help. I’ve also attached a video link:
https://youtu.be/EBLsiqEIkMg