Long time lurker, first time asker...
When we run events, our sales teams are in the habit of speaking to their clients over the phone, and when the client confirms they will attend, they offer to fill out the registration form on the contact's behalf (the form is embedded on our site, rather than a landing page). This causes issues when they do it for multiple leads, as although the form action itself completes, the flow steps to register them do not fire, so us Marketers don't know that the client has been registered, and neither does the client, as they never receive the confirmation email.
I'm presuming this is a cookie issue; as a workaround we've been asking the sales teams to submit each registration in a new Incognito window. Has anybody come across this themselves, and how did they get round it? Obviously we don't want to dispense with collecting cookies, but this can get a little frustrating!