till was working ok was turned off for 1 week for holidays came back & turned it on & no buttons work screen has 1 line of symbols across the middle wont even let me use the no sale button
how can I fix it
It sounds like the battery wasn't replaced on-time. Your dealer should replace it for you every four or so years. You have probably lost all programming and will need to RAM clear it and start again using the programming tables in the book. The information is getting difficult to find now but one of the users has all of the manuals here:
howtomendit.com for free repair help, information and advice.
Try fixfault.com to fix cash registers.