Forget the lines in production (3,2)
I believe the answer is:
dry up
'forget' is the definition.
Although both the answer and definition are verbs in their base form, I don't understand how they can define each other.
'lines in production' is the wordplay.
I cannot quite understand how this works, but
'lines' could be 'ry' (abbreviation for railway) and 'ry' is found within the answer.
The remaining letters 'dup' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
'the' is the link.
Can you help me to learn more?
(Other definitions for dry up that I've seen before include "Shed moisture or stop talking" , "Shrivel" , "Rude command to stop talking, or polish dishes after washing" , "Turn off gas" , "(Of flow) cease, stop" .)