Hi there,
Although I'm not a developer, the version number in your notification indicates you're trying to install the plugin version developed for Moodle 3.1, which is not really what you'd want. At the same time, the warning states that there's already a more up to date version of the plugin in your instance. If you're running an up to date version of Moodle (3.9 or higher) and wish to install this plugin, the version number should at least start with 2020... or 2021..., and not 2016...
Although I'm not a developer, the version number in your notification indicates you're trying to install the plugin version developed for Moodle 3.1, which is not really what you'd want. At the same time, the warning states that there's already a more up to date version of the plugin in your instance. If you're running an up to date version of Moodle (3.9 or higher) and wish to install this plugin, the version number should at least start with 2020... or 2021..., and not 2016...