Deficit the firm can't carry? (5,4)

'firm can't carry?' is the definition.
I don't know anything about this answer so I can't judge whether this works.

'deficit' is the wordplay.
I cannot really see how this works, but
'deficit' could be 'loss' (I've seen this before) and 'loss' is located in the answer.
The remaining letters 'heavy' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).

'the' is the link.

Can you help me to learn more?