I have a list populated with content type ("TypeA") with a column (site column "ColB") that originally was a single line of text. I needed to change the column to a choice instead of a single line of text.
In Site Columns, I changed "ColB" to Choice and added the options. No problem. In Content Types, I changed "ColB" to Choice (or it changed automatically, can't remember). No problem. In the listsetting, "ColB" is still listed as Single line of text. Tried to change it in both SP Designer and in the web UI, but saving changes fails both ways, and "ColB" stays as a single line of text. (And the list forms still show a plain textbox for the editor)
What did I do wrong? How can I fix this to make "ColB" a choice?