The phrase 'nature of your enquiry' is correct and usable in written English. It is typically used when someone is asking for clarification on something. For example, "Please provide more information on the nature of your enquiry."
If you are dissatisfied with the outcome you must lodge an appeal with the awarding body within two weeks of receiving the outcome of your enquiry.
From the bare bones of your enquiry I would say you have a case and ought to take further legal advice.
The nature of your degree can widen your options.
* The nature of your capital gains.
The nature of your business.
Understand the nature of your own needs.
2. Identify the nature of your apology.
Could you please clarify the origin and nature of your allele?
Determine the nature of your podcast.
Establish the nature of your doubt.
Recognize the nature of your illness.
Ludwig does not simply clarify my doubts with English writing, it enlightens my writing with new possibilities
Simone Ivan Conte
Software Engineer at Adobe, UK