He reportedly replied: "Yes, we're all absolutely watching everything, but I'm going to insist it stops before it reaches me."
The royal expert said the conversation between her and Harry happened around two years ago when the hit show was in its second series.
Speaking about the conversation with the royal, Ms Levin said: "And he's now actually doing what I think is so disloyal and rude and that is taking money from a company like Netflix that knows exactly that it's going to get its pint of blood out of somebody when it offers a lot of money.
"When he knows the same company is ridiculing his father, his mother and his grandmother."
It's not the first time she's criticised the Duke after saying previously he had "made a terrible error" for doing business with Netflix while speaking on Good Morning Britain.
She also spoke about how much Harry had changed and was almost "unrecognisable" from the person she "spent a lot of time with".
Prince Harry has previously spoken about The Crown while appearing as a guest on The Late Late Show.