Hi, thank you for contacting JustAnswer.com. My name is Russell. I will do my best to provide the right answer to your question.
I think that, by the look of it, your Handsonic has suffered a shock to its central electronic workings.
Has it been dropped? Has it been used in very hot or very cold circumstances?
Have you used it while wearing a wool sweater or other woven sweater? That can cause damaging electrostatic discharge into electronic devices, causing them to 'lock up' and display rather as your Handsonic unfortunately is.
Therefore I recommend that you turn it Off, remove the batteries (if it has any or is powered by batteries), unplug it also (if it has any connection, esp. power or USB), and leave it that way for overnight or longer. See if that gets it out of its locked-up condition.
How old is the Handsonic in question? measured from its date of purchase.