ModelCache.safeGet(androidProjectResult.androidProject::getNdkVersion, "") must not be null - android-studio

Question

When I Updated the Android Studio to the Bumblebee 2021.1.1 I got this error:
ModelCache.safeGet(androidProjectResult.androidProject::getNdkVersion, "") must not be null
I have already added ndk.dir to local.properties but I still have the error.
sdk.dir=/path/to/sdk
ndk.dir=/path/to/ndk

Answer 1

Add ndk path in android.ndkPath
Or
Add ndkVersion '23.0.7599858' (If you use this approach then in some case you have to add version in other library module if they use ndk)
You can also add this using File-> Project Structure

Answer 2

The value for ndk.dir should no longer be set in your app's local.properties file, and support for this ndk.dir setting will be removed in a future version. The Android Gradle Plugin sets the NDK version by default, but if you need a specific version of the NDK, you can set android.ndkVersion in build.gradle.
Remove ndk.dir=/path/to/ndk from the local.properties.
go to build.gradle under android section add ndkVersion='required ndk version'
ex:
android {
ndkVersion '23.1.7779620'
}
Reference : Android office doc's

Answer 3

Google has provide this fix in Android Studio Bumblebee | 2021.1.1 Patch 2 (Issue link)
So, updating my Android Studio to Bumblebee patch-2 solved this error.
Now I need not to add the ndk paths as suggested in other answers.
Google Android Studio changelog

Answer 4

ndk.dir=/path/Android/Sdk/ndk
sdk.dir=/path/Android/Sdk
Try to define like this

Answer 5

Follow these two steps to solve the issue
Go to SDK Manager>SDK Tools> NDK > Uninstall all
Go to the ndk directory and see if it's empty, If it is not, delete the files
Install a new copy of ndk from SDK manager
in your local.properties gives your path as
sdk.dir=D\:\\AndroidFiles
ndk.dir=D\:\\AndroidFiles\\ndk\\23.0.7599858