BANDWIDTH LIMIT EXCEEDED! HELP!

My daughter @briannalaney is having trouble with her account. She cannot post, edit, comment, upvote. Nothing. No warning whatsoever. It just says "Bandwidth limit exceeded. Please wait to transact or power up STEEM." What does it mean? Any of you encountered something like this? What should we do?

We're neophytes in this platform and we will appreciate any sound advice and spot on solution to this. Thanks in advance!