If you mean that "H1 Mitigation" as a collection of H1 Mitigation Blocks, you actually have it drawn slightly wrong. You would need to move it up 1 Candle from where it starts on the Left Side.
That's a Bearish H1 OB that has a "bad" H1 Bullish OB within it. So it did return to Mitigate an OB, but it wasn't much of an OB. That's actually a Range Break/Market Structure Break move, so the actual pull back was a mitigation itself. (Just being Technical.

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