import dependency

Idea intellj 导入maven依赖包
默认情况下，pom.xml变化时，idea 会提示 Auto-Import for Maven projects，点击下载依赖

开启自动加载
File > Settings > Maven > Importing, there is a checkbox that says “Import Maven projects automatically”.

使用命令行加载
If that doesn’t help, then I would suggest to make a full clean-up and start again:
Close your project window (and IntelliJ) and remove all *.iml files and all .idea folders (there should be one per module)
Run mvn clean install from the command line
Re-import the project into IntelliJ and pay attention when it asks you to enable auto-import