I am new to this forum and am looking for advice on hardwood floors. We want to install new red oak floors in our home. My brother had his floors installed new and the lower level was screened and finished. There are some issues with the old floors. I am attaching a few pictures and was hoping someone had an idea of what went wrong. The floors were done almost one year ago and it has areas where the finish is coming up. What can cause this to happen?