I think that Endercore has been updated, possibly due to a vulnerability.
dogboy21/serializationisbad#36

When I create a Aternos Minecraft Server with the Levitated Modpack (1.5.3), it says:
Server Mod Rejections:
EnderCore: Requires version 1.12.2-0.5.77 but client has 1.12.2-0.5.76

@FrinkTheBrave: Hello! 👋

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