Website not remembering my local storage settings after clicking "Allow"

I use [link removed], which is a chat site.  Recently I've noticed that my conversations there keep getting cleared and that flash pop-up comes up everytime I want to send a message, asking if I want to allow the site to store information on my computer.  I always click Allow, but the same thing keeps happening everytime I visit the site;  it's not remembering my storage settings.

My question is:  Is there a way to increase the amount of information the site can store on my computer? (currently it is at 750bytes)

Or if not, is there some step that can make the site remember the settings I set for it?  I have gone into global settings and the option is already selected to allow sites store information on my computer, so I'm not sure what else I can do.

Any help would be appreciated, thank you in advance.  I'm tired of my conversations on chatango getting deleted all the time.