ok so when I use this macro on my shadow priest, it works perfectly as it shows

/assist party1
/castsequence [nochanneling] reset=target Vampiric Touch, Vampiric Embrace, Shadow Word: Pain, Mind Blast, Mind Flay, Mind Flay, Mind Blast

and when I use this macro with my shammy, it also works perfectly

/target party1
/castsequence [target=targettarget, harm] [target=party1] reset=5 Rejuvenation, Moonkin Form, Moonfire, Insect Swarm, Wrath, Wrath, Wrath, Wrath, Wrath, Wrath

But when I use this one on my shadow priest it goes through everything fine but the chanelling doesn't work..

/target party1
/castsequence [target=targettarget, harm] [target=party1] [nochanneling] reset=5 Renew, Shadowform, Vampiric Touch, Vampiric Embrace, Shadow Word: Pain, Mind Blast, Mind Flay, Mind Flay, Mind Blast

Can anyone tell me what I'm doing wrong?