Immersive Portals not allowing server joining after uninstall

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    I was using Immersive Portals on my server, and decided to remove it in favor of a different portal mod since it was incompatible with Taterzens (an NPC mod). After uninstalling it both from my Aternos server and my fabric modpack (running via CurseForge), I am unable to join my server and I am getting this error. I made 100% sure that there were no portals left over, and nobody had any of the modded items still in their inventories. Please help; I'm worried I may end up losing my world because of this!

    Looking into it a bit further, it seems that the blocks/items are somehow saved into the world's data despite not being placed, and that's whats causing issues...

    Try deleting the config folder which is in the minecraft installation path

    I 100% did. I even went into the files on Aternos and removed any remnants of config/whatnot.

    I'm trying a fix now where I reinstall it on both, try some commands to find & remove any blocks I may have missed, uninstall it again & try reloading.