Is this a new building or old.
If new does it flood every time it rains.
If old is this the first time it’s flooded due to the exceptional weather if so it’s an insurance claim. Strata insurance for the wardrobes, walls and other fixtures in the lot and contents insurance for carpets and personnel items. This assumes your insurance covers floods. If your insurance doesn’t cover floods you have a claim against the strata as they are responsible for insuring the building and they have failed.
Why do you expect it to flood again if it was due to an exceptional storm which is not likely to recur or is this an ongoing problem.