The skin does not exist: Unable to determine the release version

hi I have problem generating site when im using the command mvn site

it performs all stagegs and when it came to site generation the message is shown :

The skin does not exist: Unable to determine the release version

Try downloading the file manually from the project website.

Then, install it using the command:
mvn install:install-file -DgroupId=org.apache.maven.skins -DartifactId=maven
-default-skin \
-Dversion=RELEASE -Dpackaging=jar -Dfile=/path/to/file

org.apache.maven.skins:maven-default-skin:jar:RELEASE

do u have an idea what is the problem ?

p.s the jar is registered in my local repository and in the remote repository

thank u