Path changes when Object is rotated in timeline

So I am following a course and currently we are developing an 3D rail shooter . So when I animate my player using timeline it runs fine until I rotate the player. If i rotate it at a key frame it completely changes its path. Check the video below for visual representation. I know this might be a really basic problem but I am relatively new to game development and its my first time using timeline and animation. I would really appreciate a solution.