I don’t bother to insert the key attached to it (4,2)

'i don't bother' is the definition.
I don't know anything about this answer so I cannot tell whether it can be defined by this definition.

'insert the key attached to it' is the wordplay.
'insert the key' becomes 'ied' (I can't justify this - if you can you should give a lot more credence to this answer).
'attached' becomes 'on' (I've seen this in other clues).
'to' means one lot of letters go next to another (I've seen this in other clues).
'it' becomes 't' (abbreviation. e.g. in 'tis).
'ied'+'on'='iedon'
'iedon' after 't' is 'TIED ON'.

'to' is the link.