Field name change not appearing in formula builder


I have a field that consists of a formula that multiplies numbers from two other fields. (Neither of these fields are in the first “name” field.) I changed the name of one of the number fields to a better description. The original formula in the formula field still shows the old name for the number field that I changed, and it still works. However, I needed to change the formula in th formula field, but when I did, Airtable insisted that I use the old number field name instead of the new changed one. Furthermore, the drop-down list of fields in the formula builder dialog box still had the old number field name listed and not the newly changed name. This seems confusing because, even though I changed the number field name, it appears that I still have to remember what the old field name was and continue to use that old field name in the new formula field.

Is this the way it is supposed to work? Or is it a bug? I thought that a changed field name would be reflected everywhere, including the formula field builder.