Asked to pay but sick in bed (6)
I believe the answer is:
billed
'asked to pay' is the definition.
I can't judge whether this defines the answer.
'sick in bed' is the wordplay.
'sick' becomes 'ill' (synonyms).
'in' indicates putting letters inside.
'ill' put inside 'bed' is 'BILLED'.
'but' acts as a link.
Can you help me to learn more?
(Other definitions for billed that I've seen before include "Listed in a programme; charged" , "Caressed" , "Advertised" , "Sent an invoice" .)