Sorry for the trouble! You need to simply Deactivate the plugin first, then the update link will show. The plugin thinks it is a Premium version, which prompts for licensing it first, which is incorrect, and v1.5.4 fixes that problem.
When you click Deactivate, you may get a pop-up asking why you’re deactivating just as a survey, you can click “Skip and Deactivate” or you can click “Temporary Deactivation” etc.
Once deactivated, it will update as normal, and the issue will be resolved.
Optionally, you can also just delete the plugin using FTP or your hosting File Manager, and then search/install it fresh.
Apologies for the trouble.