Good afternoon. 

It seems like you accidentally changed access tags for all streets in this neighbourhood from private to no based on some QA flag, making the entire area unroutable. 

When trying to solve issues remotely it's usually very helpful to look at way histories. In this case the cause of the sink island was caused by an incorrect oneway tag on the entrance street.

Also, "fix street" is not a very meaningful changeset comment. Please have a look at: https://wiki.openstreetmap.org/wiki/Good_changeset_comments

Thanks!