Appointments+ user submitted names getting mixed up

Hi guys! We're using Appointments+ on a Driver's Training website. They're having issues where the wrong name is ending up on the schedule, from my client (I edited this down):

We have issues sometimes where appointments+ inserts the owner of the e-mail address' name, rather than the submitted name (who the appointment is actually for). We just had a situation where the registration came through with an applicant name, his mother's name was different and on the schedule is a third different name. This is not the first time someone else's name showed up on the schedule but usually it is the parent's name so we could trace it and change it.

Any idea what could be causing this? I just ran whatever the latest update was for Appointments+, but didn't see anything related in the change log, so I'm not sure if that'll fix it,

thanks,
Will

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