May have made a bit of a boo boo

Recently I’ve been casting a curse to weaken and get rid of two people. I went about this by first breaking the will of my targets and then drawing out their life energy and pushing them into insanity until their mind breaks completely, with the help of a few lesser spirits.
All has gone well, in so much as my targets sanity is slipping hugely now. However in their decent into madness they’ve become more unpredictable and this is now effecting the person I’m casting it for.
I’m torn between just finishing him off and hoping my client is fine or pulling back for a bit. It’s just a free favour for someone btw

I’m still a student of these arts, but I’d continue dropping their sanity, and ask you friend to hold on, and finish them off quickly.