Drying while you’re phoning (2,3,4)
I believe the answer is:
on the line
'phoning' is the definition.
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for on the line that I've seen before include "Using the phone" , "Caller may be" , "when one is at risk" , "At risk - or speaking on telephone" , "At serious risk" .)