I was burnt out in the 2009 Victorian Bushfires. I was part of a group to claim for damages. February 2015, I received the final distribution of settlement funds. I then had work done on the house and property and organised an overseas holiday. Six (6) weeks later I received a letter from the Solicitors stating "that there was an error in our calculation of the final distribution to you". They now want $17, 137.00 back as is it was paid to me in error. I now do not have the money, am unemployed and still have a mortgage to pay as well. Do I have to pay it back? If so, can I pay it back in instalments on a regular basis without accruing interest?