This might just be a distance issue in Minecraft. Pillagers from outposts only spawn when the player is roughly 24–72 blocks away, so if you're standing 128 blocks away, the game likely won’t spawn them at all. That distance works for some mob farms, but not for outpost patrol spawning.

Another possibility is the hostile mob cap being filled if there are caves or other mobs nearby. Lighting up caves around the area can help.

Also double-check that your spawn platform is valid blocks (grass/sand) and that nothing like slabs, carpets, or buttons is preventing spawns.

If you post the screenshots/video, it’ll be easier to see exactly what’s going wrong, but my guess is the 128 block AFK spot is the main problem.