I am a finalist at two very good schools to work at, and asked my previous supervisor, switched departments, if I could put him down as a reference. He said yes. He gets notified by these two schools and texts me this.
Him: Hello _, I cannot be your reference while you are employed at _,
Me: _,, you said yes. I already but you down. Me being employed at _, should not be an issue.
Him: sorry, I can’t.
Me: You said yes. You would really cost me a potentially good job? And because of what?
Me: There’s no rule that says you can’t be my reference. I already put you down. You had told me yes.