If you cannot uninstall it, rename the folder name of the module modules/modulename/ as modules/bug-modulename/. Delete file override/controllers/front/ProductController.php and delete folder var/cache/prod or var/cache/dev if you are in debug mode.
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If you cannot uninstall it, rename the folder name of the module modules/modulename/ as modules/bug-modulename/. Delete fiel override/controllers/front/ProductController.php and delete folder var/cache/prod or var/cache/dev if you are in debug mode.