PC Why Did It Happen

I was doing a Scenario Planner and when i spawn in i got spad

 

Have you checked consist lengths? It may be a good idea because perhaps it is too long to fit in a signal block.

Alternatively, you could disable each service one by one to find out which one is causing the SPAD, but that may take a while.

 

But the train is in front the signal

 

Are there any other trains set up for AIs in the scenario? I believe that if any train in the game SPADs, it'll end the game so if they're dropping in to an unavoidable red, you'll get booted out.

 

Factor41 is correct. If a non-player train passes the signal at danger, then it will fail the scenario. The fact that this SPAD happens immediately is very confusing, but I would suggest checking consist lengths and whether or not the train fits (and doesn't roll forwards at all.)