Crossword Genius

When I floated off, didn't (6,2)

Ross

I believe the answer is:

failed to

I'm a little stuck... Click here to teach me more about this clue!

'off didn't' is the definition.
I know nothing about this answer so I can't judge whether this works.

'when i floated' is the wordplay.
'i floated' can be anagrammed to 'FAILED TO'.
But, I am not sure how the anagram is indicated.

Can you help me to learn more?

I've seen this clue in the Evening Standard.
Want a hint initially instead of a full solution? Install my app