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This, no need to replace if it worksIf it seals it works
What’d you do to it?
Are you looking at the flat edge on the inside of the o ring? If so, that's designed and should not affect sealing. It gives you space to insert a pick to remove the o ring.
Momentary leaking prior to lockup is not uncommon especially at lower pressure. As others said, if it seals it's good.