I had something similar happen once—my footer image suddenly stopped scrolling smoothly and just popped into place. What helped in my case was clearing the browser cache and then reopening the Wix Editor. That fixed it for me!
If that doesn’t work, another quick step is to reconfirm the animation settings (like start/end positions) or temporarily toggle the animation off and on again to refresh its state. Sometimes a hard reload of the page after republishing does the trick too. Let us know if any of that helps! you can alos check this thread Slide Animation Not Working When - Slide From Bottom Option Is Selected