Rental income diverted

My sister and I inherited a property from my late mother; and with that tenants and a lease agreement with AIDA. The property is in both our names.

My sister caused an administrative mess; which almost ended up with myself being on the receiving end of a lawsuit by the body corporate. In order to avoid any such issues in the future I immediately tried to take control of my finances.

Only to be told by AIDA that they will not split the payout of the rent between my sister and myself.

I spoke to the director of the rental department (conversation recorded) who told me to sort things out with my sister. The law prohibits me from detailing my sisters health issues but this is not an option.

I have spoken to other estate agents; and according to my knowledge AIDA is the only estate agent unable to split payments.

Please assist; my sister and our issues are non of AIDA's business to manage. Furthermore my sister is very ill, she is not a financial institution and could be hit be a car tomorrow.

Kind regards