Still doubtful and not to be depended on (9)
I believe the answer is:
uncertain
'still doubtful' is the definition.
'uncertain' can be an answer for 'doubtful' (similar in meaning). I'm not certain of the 'still' bit.
'not to be depended on' is the wordplay.
'not' becomes 'un' (I've seen this in other clues).
'to be depended on' becomes 'certain' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'un'+'certain'='UNCERTAIN'
'and' is the link.
Can you help me to learn more?
(Other definitions for uncertain that I've seen before include "up in the air" , "Lacking confidence" , "Not definite" , "Not at all sure or decided" , "Doubtful, indecisive" .)