Overpayment



Over the last year due to two reassessments and the usual CSA incompetence I have now overpaid my CSA 'bill' by £345.32, (based on their assessment of liability) they collect through DEO so I have no ability to change the payments, two letters and an email have received no acknowledgement, is there a proper procedure to get back this money or have I just got to kiss it goodbye?
any help appreciated
thanks
John

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