How do you update? Automatically via the admin menu?
Did you restart your browser and clear the cache just to make sure?
Check in the plugin editor if the version in the file is the correct one. To do that, go into the admin dashboard, in the plugin menu, go to “Editor” then select your plugin on the top right dropdown. The first file should be the main file, and in the top of the file there should be something like
<?php
/*
Plugin Name: my plugin name
Version: 1.2.2
Check if that’s the latest version. If not, you do not have the right files on your server.
If that is what fails can for example manually remove it and copy the latest version in via FTP or file mananger, whatever is appropriate for your environment.