Failure to decide about new uniform again did puzzle Head (14)

'failure' is the definition.
Both the answer and definition are singular nouns.
Perhaps they are linked in a way I don't understand?

'decide about new uniform again did puzzle head' is the wordplay.
I cannot really see how this works, but
'decide' could be 'resolve' (resolving is a kind of deciding) and 'resolve' is located in the answer.
'new' could be 'n' and 'n' is located in the answer.
'uniform' could be 'u' (phonetic alphabet: alpha, bravo, charlie etc.) and 'u' is found in the answer.
'head' could be 'ness' (ness is a headland) and 'ness' is found in the answer.
A single letter 'd' remains which might be clued in a way I don't understand.
This explanation may well be incorrect...

'to' is the link.

Can you help me to learn more?