incompitent service

my father booked for a trip using Agoda and paid the full amount for him to go on vacation unfortunately my mom fell ill two days before the actual trip we then called the CallCentre and where provided with requirements to amend the booking and choose different dates ,we then sent all the requested documents including a letter that my mother was admitted to the hospital from a registered doctor but we getting no joy ,yesterday we received an email stating that the partner which is the hotel they booked at (GARDEN COURT DURBAN )CANNNOT amend the dates how so when my dad also forwarded documents to garden court and was assisted by a lady by the name of NTSIKI , AND U STATE U CANT AMEND ...this needs to be fixed as my parents spent a lot of money on that booking ... I need a supervisor to fix this fast because all the requirements were met, or I will take this further.