Hi Manuela,
That message is just letting you know that anyone who you register on the backend via planner mode as you have shown in your screenshots will be counted towards your contracted registration numbers just like if any attendees were to register for the event themselves on the front end.
With abandoned registrations, once someone makes it past the first page of registration, every time they click Next their work on previous pages is saved for a week, so I am guessing in this scenario it had been longer than a week since that person originally entered in their information. Managing Abandoned Registrations
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Julia Plymack
Senior Customer Success Manager
Cvent
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