How To Stop Sending Endorsement Requests
If you've accidentally invited your contacts to endorse you, you can cancel any pending invitations that haven't been sent yet.
Considering that Gainrep dispatches invitations at a consistent rate, you usually have a window of time to cancel them. To do this, navigate to the "Reputation / My Network" page and search for the "Pending invitations" menu.

Here, you can cancel all invitations at once or just a specific one.
If the "Pending invitations" menu is not visible, it indicates that all invitations have been dispatched, and there are no pending invitations to cancel or to be sent in the future.