I would go back to basics if I were you.
Get a long line (a 60' horse line would be ideal) and keep her on the line. Let her have some freedom and then call her back, reeling her back in so to speak.
An incentive would be a reward of warm sausage, baked liver, ham etc - something very desirable.
She's probably being a teenager. Marlon went through a phase like that between about 9 - 13 months old and everything he learned he unlearned!
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