Hi, would like to seek some advice on water leakage repair here.

I had a newly VP unit with water leakage issue above one of the bathroom. Developer came over to fix one time but water stain appeared again and I complained to them again .

So I noticed that they had opened the ceiling to the bathroom and this is how it looks like. Seems like there are water leaking out of the wiring hole.



When I came again the following day I saw that they had made some patching with a cement like substance (water plug?) and they had a sponge taped to the piping too.





I'm not sure what exactly they tried to do. Would anybody with plumbing knowledge explain? If this the right measure to rectify the leakage?

Also I wonder if this black cover is normal? I asked other residents and it seems like they do have the same black cover as well.

The sponge could be temporary. I need to check on my unit again to see what is their progress. The pictures were taken last Monday.

I asked management (developer) to provide me the inspection report but no reply from them till now.

Would you have any idea on the black cover thingy?