Web animations not working on mobile devices

Today I updated my website, but I found that all the web animations are not working on my phone (iPhone6, IOS12.4.5, iPhoneXS, IOS12.0.1)!!! Everything was fine before this. How can I restore it to its original state?
I tried to restore the backup, but the web animations are still not working (I tested the source code copy saved a few months ago, and the web animations in it are normal).