Relink Account notification is automatically enabled in your My Settings to ensure that your shares are always sharing correctly to your social networks.
If a share fails, you will receive an email and an in-app notification letting you know that the post did not go through. When this occurs, go to your Settings, scroll down to Social Settings and click Relink for your LinkedIn account.
If you want to disable this setting, go to My Settings and scroll down to Notification Settings to turn the toggle off for 'Relink Account'.
And remember to scroll to the bottom of the page and click Save Settings: