Hi @juliekelso
Is the Start/Pause button blinking when it stops and if so what colour is it when it blinks?
Here's the [document|32359|service manual] that may help.
''If the Start/Pause button is blinking'' go to p.45/176 to view how to interpret what error code the blinks are indicating. The error codes and the possible causes are shown on p.46/176 →p.49/176.
''If it isn't blinking'' then go to p.5 to view rhe procedure tio access the diagnostic cycle and run the diagnostics tests to hopefully find out what's wrong.