Confused by lookup field

I have a status field that I use to track the reservation record.

I have a couple of statuses that I write via script that I do not want to be set by a user. So in my lookup table I only included the statuses I want the user to set. If I create a new record or edit a record I also see the statuses that I have written via script in the lookup field choices it is not just the values from the lookup table. Why is it showing these extra values. That does not make sense to me. Is there a simple way to make sure it is showing the statuses from the lookup table?

Shadrach