U200 underpinner - not firing v nails

[Gemmie123]

Hi
Anyone had this issue after switching to different head ?
It isn’t lifting a v nail at all , I can see the part that pushes the v nail up, but no v nail is being fired
Switched back to the other size that I have been using without issue and it’s the same - won’t lift a v nail
All instructions followed , and have emailed Alfamacchine support but posting incase anyone else had experienced same and I’m missing something .

Thanks in advance

[Gemmie123]

Fixed