Incurring a bill for the making of, fast (7,2)

I believe the answer is:

running up

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'making of fast' is the definition.
The answer and definition can be both related to change as well as being present participle verbs.
Perhaps there's a link between them I don't understand?

'incurring a bill for' is the wordplay.
'incurring' becomes 'running' (running is a kind of incurring).
'a bill for' becomes 'up' (I can't explain this - if you can you should give a lot more credence to this answer).
'running'+'up'='RUNNING UP'

'the' acts as a link.

Can you help me to learn more?

(Another definition for running up that I've seen is " coming after 21 [WINNER]".)

I've seen this clue in the Evening Standard.

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