in plugin page there is an available update from 5.6.9 to 6.2.0, but when I clic on UPDATE I receive the following message: You have installed the last version of plugin. How this is possible?
To be honest with you we change the domain name from (janegoodall-italia.org) to (janegoodall.it).
Have you had LayerSlider installed as a bundled item in your theme earlier ? Some themes are restricting the update and/or activation of the plugin that could result in problems like this.
I'd recommend to manually update the plugin by downloading the newest release from CodeCanyon and reinstalling LayerSlider. Your sliders and settings are stored in the database so they won't be deleted in the process.
You can also find installation instructions in the documentation: https://support.kreaturamedia.com/docs/layersliderwp/documentation.html#plugin-setup
I've done what you said and It's work!