Hi,

I already replied in your mail.  The 15gb is your personal free space which has a separate allocation from the shared drive.  You may try to upload a large file inside the shared drive/folder to see that the 15gb free personal space won't be affected as the shared drive has an unlimited space.  Just make sure that you put the files inside the shared folder I've created.  I can't understand the language in your screenshot but I believe you put the files inside one of your personal folders (My Drive or the first one that is the highlighted) and not inside the shared drive.

Btw, thank you for purchasing and for the trust.