All WonderPlugin Products
I purchased the commercial version and have received my membership login password. I downloaded the commercial version and followed the upgrade instructions as posted on your website, however, the free version watermark remains.
Firstly, please goto the plugin menu Overview, check the title of the plugin. For commercial versions, it should say "WonderPlugin PLUGIN_NAME Commercial Version VERSION_NUMBER C".
If it still shows "Free Version", then it means your website is still running the free version. Please follow this tutorial to upgrade: https://www.wonderplugin.com/wordpress-tutorials/how-to-upgrade-to-wonderplugin-commercial-version/
If the title is correct, then it's normally a cache issue. There may be four caches that you need to clear.
1. Web server cache by your web hosts. Some web hosts will cache web files, for example, GoDaddy, WPEngine and DreamHost. Please contact your web hosting provider and ask them whether the web files are cached and how to clear the cache.
3. Your local web browser cache. Please clear caches of your web browser after you upgrade the plugin.
4. CDN sync. Some web hosting providers use CDN to deliver image and js files. In this case, you need to force to sync your content to all CDN servers. If you are using a CDN, please contact your web hosting provider for how to do this.