Youtube Comments Orders Getting Cancelled ?

I Bought youtube comment service from many sellers as well as bunch of sites like -smmstore, smmglobe, instantpanel, instant-fans and many more but as soon as i buy comments they get cancelled within 5 mins & i made support ticket also but they don't know why is this happening. Random Comments are working fine but custom comments gets cancelled each and every time. I don't know why is it happening maybe because of any recent youtube update or something, i don't know.

Is this happening with me only or anyone else got in this situation, also please tell me is there any comment service still working i can try ?

Thanks