When I finished downloading the official demo project, after opening the project import plug-in, the project still could not run, and the following error was reported.

Library\PackageCache\com.unity.textmeshpro@2.1.4\Scripts\Runtime\TMP_DefaultControls.cs(188,22): error CS1061: 'RectMask2D' does not contain a definition for 'padding' and no accessible extension method 'padding' accepting a first argument of type 'RectMask2D' could be found (are you missing a using directive or an assembly reference?)

I want to know how to solve this problem.

Make sure you're using a compatible Unity and a verified TMPro package versions.

How should I check my package version and compatible unity.

Here is more info on that: https://naninovel.com/guide/compatibility