Formal complaint regarding Graduation department

I overpaid for the hiring of my academic regalia and The Graduation department of the Potch campus told me to fill in a refund form with my POP and I sent all the relevant documents afterwards there was no communication whatsoever and I graduated in March and was told by April my refund would be finalized it’s June now and there has been no responses to my emails why does one have to wait months for a refund ???!!!