UParticleSystemComponent. setting the Source/Target point C++

Hi, I’m relatively new to UE4 and creating a little game to help learn and develop my knowledge in UE4 engine. I cant seem to figure out why when I am setting the source/target end points it is not working. I have seen multiple forums say it needs to be user set but i’m having no luck with it. Apologies if it is some silly :slight_smile:

Thanks in advance