Cant add new website

I am trying to add a new site to monitor. This site is one that I have previously deleted in error. However, when I name the site, enter the URL, and press Save, Piwik does not retain the data and does not display my new site in the Dashboard.

Any ideas as to why this is occurring?

well me neither

You have to press the green icon on the right side, not the save button below. This is a known point of confusion and will be tackled by some redesign in near future.

I am trying to add a new site to monitor. This site is one that I have previously deleted in error. However, when I name the site, enter the URL, and press Save, Piwik does not retain the data and does not display my new site in the Dashboard.

Any ideas as to why this is occurring?

I had the same problem and had a friend sort this out for me.
I think as Fabian commented above this was the issue that corrected mine.