Unable to merge android manifests

I got the error on compile and I can’t fix this no mater what I try.
I already set Minimum API level in Other Settings to 15.

It says …/Temp/StagingArea/android-libraries/GoogleMobileAdsPlugin/AndroidManifest file has but library uses minSdkVersion=‘15’.

But the file actually has . So do the other 3 AndroidManifest files on the error report.

Can anyone help me with this error? Any advice will be so appreciated.

The whole error msg is …

Error building Player: CommandInvokationFailure: Unable to merge android manifests. See the Console for more details.
/Library/Java/JavaVirtualMachines/jdk1.8.0_25.jdk/Contents/Home/bin/java -Xmx2048M -Dcom.android.sdkmanager.toolsdir=“/Users/davidkim/android-sdks/tools” -Dfile.encoding=UTF8 -jar “/Applications/Unity/PlaybackEngines/AndroidPlayer/Tools/sdktools.jar” -

stderr[
Error: [Temp/StagingArea/AndroidManifest-main.xml:7, /Users/davidkim/DHK/Unity/SweetBlast2 (2)/Temp/StagingArea/android-libraries/ChartboostSDK/AndroidManifest.xml:3] Main manifest has but library uses minSdkVersion=‘15’
Error: [Temp/StagingArea/AndroidManifest-main.xml:7, /Users/davidkim/DHK/Unity/SweetBlast2 (2)/Temp/StagingArea/android-libraries/GoogleMobileAdsPlugin/AndroidManifest.xml:2] Main manifest has but library uses minSdkVersion=‘15’
Error: [Temp/StagingArea/AndroidManifest-main.xml:7, /Users/davidkim/DHK/Unity/SweetBlast2 (2)/Temp/StagingArea/android-libraries/facebook-android-sdk-4.7.0/AndroidManifest.xml:3] Main manifest has but library uses minSdkVersion=‘15’
Error: [Temp/StagingArea/AndroidManifest-main.xml:7, /Users/davidkim/DHK/Unity/SweetBlast2 (2)/Temp/StagingArea/android-libraries/facebook-android-wrapper-release/AndroidManifest.xml:3] Main manifest has but library uses minSdkVersion=‘15’
]
stdout[
[Temp/StagingArea/AndroidManifest-main.xml, /Users/davidkim/DHK/Unity/SweetBlast2 (2)/Temp/StagingArea/android-libraries/GoogleMobileAdsPlugin/AndroidManifest.xml:10] Skipping identical /manifest/application/meta-data[@name=com.google.android.gms.version] element.
[Temp/StagingArea/AndroidManifest-main.xml, /Users/davidkim/DHK/Unity/SweetBlast2 (2)/Temp/StagingArea/android-libraries/MainLibProj/AndroidManifest.xml:16] Skipping identical /manifest/application/meta-data[@name=com.google.android.gms.version] element.
[Temp/StagingArea/AndroidManifest-main.xml, /Users/davidkim/DHK/Unity/SweetBlast2 (2)/Temp/StagingArea/android-libraries/google-play-services_lib/AndroidManifest.xml:5] Skipping identical /manifest/application/meta-data[@name=com.google.android.gms.version] element.

search in all AndroidManifest files in your project and set <uses-sdk android:minSdkVersion='*'>
to same value 15 <uses-sdk android:minSdkVersion='15'>