You can try replacing the wax ring. Usually, that will fix the type of leak you describe. Essentially, there is a wax gasket which seals the area between the flange (in the floor) and the porcelain (on the bowl). Due to age/movement/etc, this gasket will eventually fail, and cause leaking when the toilet is flushed.
This is within the wall of the condo unit, so this would not be an association expense, but an expense for the owner to pay. It is essentially wear and tear of the gasket.
Submit an email to support@prorealtyteam.com or call 8882301578 ext. 2 and leave a message for customer support to assist with repairs.
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