We've noticed a little quirk in Procreate that can throw off the authentic look of halftones when you're working in Procreate.
Here's a little known trick for you to make perfectly aligned halftones in Procreate using ColorLab Comic Halftone textures and DupliTone Halftone brushes.
When you adjust halftone size in Procreate, do not adjust the size of halftones with the Grain Scale slider. They will not overlap correctly and the authentic halftone effect will be lost.
Instead, write in or type your percentage when adjusting halftone size so they align properly.