WPMU Multisite site storage quota

Hi Guys
Your support has been great thus far.
Please can you urgently get back to me with regards to the site storage quota limitation we are getting on our main site in the multisite network.

It says we have exceeded our 100mb quota and cannot upload any more images. We need to launch soon and need this problem sorted. I have tried everything, including network setting for limit mb as well as individual site where i edited the settings at the bottom to increase space, nothing is working. Please help urgently