I need help.
Brush is pixelating when i apply on mask.
brush properties are fine and smooth option is also enabled.
Could be a texture in the brush. Anyway, whatever it is, see if it goes away if you activate Brush Tool then right-click its icon at very left of Options bar and pick Reset Tool from the menu that appears, as in screenshot below.
This is an artefact in the way the mask is displayed when viewing against the transparency grid. Put a plain white layer underneath to check and you should see that it disappears.
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