link shows maintenance mode even if the plugin is off

Hello,

I have a link on a page that is sharing my page on facebook.
Although when it is clicked it will show “maintenance mode” instead of the link I added and picture.
Can anyone please tell me how to solve this?
The maintenance mode is currently deactivated and the page has been purged from cash but it is still showing maintenance mode.

Help much appreciated. Thanks

https://wordpress.org/plugins/wp-maintenance-mode/