FTP Builder plan help

I am doing a FTP builder plan and last night was strenght day. evertytjhing was fine until the 10 sec at 360 wts intervals came around. It read " spriint in big gears ".
The only way i could get up to the 360 wts was to increase cadance. i was spinning like a mad man and thats not strenght work.
is there a bug in the FTP builder program.

Turn ERG-mode off just before the sprint interval, choose your gear and sprint in a big gear. After the sprint, you can turn ERG on again.