My RobloxStudio have some bug with AnimationEditor? its have a glicth i can't create animation

Ever since the new update to the animation editor it was never the same. A lot of developers left this one behind and moved onto other animation editors due to all the bugs and such. To avoid problems such as this one, I think you should switch! Here's a two of the most popular animation plugins that I recommend you try.

Legacy Animation Editor(The old roblox animation editor): https://www.roblox.com/library/1882309978/Legacy-Animation-Editor

Moon Animation Suite(Has a lot more features that the other one but it's for more advanced users):

https://www.roblox.com/library/745786060/Moon-Animation-Suite