Error with authentication in mojang running in online mode=False

Hello, I've been getting problems with a sv I initialized myself with some friends, we don't have minecraft premium so we had to put it in online mode false and later this problem appears anytime someone try to join can somebody help me?:
[28dic2020 10:09:55.371] [Server thread/WARN] [net.minecraft.server.dedicated.DedicatedServer/]: **** SERVER IS RUNNING IN OFFLINE/INSECURE MODE!
[28dic2020 10:09:55.373] [Server thread/WARN] [net.minecraft.server.dedicated.DedicatedServer/]: The server will make no attempt to authenticate usernames. Beware.
[28dic2020 10:09:55.375] [Server thread/WARN] [net.minecraft.server.dedicated.DedicatedServer/]: While this makes the game possible to play without internet access, it also opens up the ability for hackers to connect with any username they choose.
[28dic2020 10:09:55.379] [Server thread/WARN] [net.minecraft.server.dedicated.DedicatedServer/]: To change this, set "online-mode" to "true" in the server.properties file.
[28dic2020 10:09:55.531] [Server thread/INFO] [net.minecraft.server.dedicated.DedicatedServer/]: Preparing level "world"
[28dic2020 10:09:55.832] [Server thread/INFO] [net.minecraft.server.MinecraftServer/]: Preparing start region for dimension minecraft:overworld
[28dic2020 10:09:56.872] [Server thread/INFO] [net.minecraft.world.chunk.listener.LoggingChunkStatusListener/]: Preparing spawn area: 0%
[28dic2020 10:09:56.872] [Server thread/INFO] [net.minecraft.world.chunk.listener.LoggingChunkStatusListener/]: Preparing spawn area: 0%
[28dic2020 10:09:56.875] [Server thread/INFO] [net.minecraft.world.chunk.listener.LoggingChunkStatusListener/]: Preparing spawn area: 0%
[28dic2020 10:09:57.590] [Netty Server IO #1/INFO] [net.minecraftforge.fml.server.ServerLifecycleHooks/SERVERHOOKS]: Disconnecting Player (server is still starting): Server is still starting! Please wait before reconnecting.
[28dic2020 10:09:57.597] [Server thread/WARN] [net.minecraft.network.datasync.EntityDataManager/]: defineId called for: class its_meow.betteranimalsplus.common.entity.EntitySongbird from class dev.itsmeow.betteranimalsplus.imdlib.entity.util.EntityTypeContainer
[28dic2020 10:09:57.959] [Server thread/WARN] [net.minecraft.network.datasync.EntityDataManager/]: defineId called for: class its_meow.betteranimalsplus.common.entity.EntityBadger from class dev.itsmeow.betteranimalsplus.imdlib.entity.util.EntityTypeContainer
[28dic2020 10:09:58.020] [Server thread/WARN] [net.minecraft.network.datasync.EntityDataManager/]: defineId called for: class its_meow.betteranimalsplus.common.entity.EntityGoose from class dev.itsmeow.betteranimalsplus.imdlib.entity.util.EntityTypeContainer
[28dic2020 10:09:58.076] [Server thread/WARN] [net.minecraft.network.datasync.EntityDataManager/]: defineId called for: class its_meow.betteranimalsplus.common.entity.EntityBoar from class dev.itsmeow.betteranimalsplus.imdlib.entity.util.EntityTypeContainer
[28dic2020 10:09:58.091] [Server thread/WARN] [net.minecraft.network.datasync.EntityDataManager/]: defineId called for: class its_meow.betteranimalsplus.common.entity.EntityPheasant from class dev.itsmeow.betteranimalsplus.imdlib.entity.util.EntityTypeContainer
[28dic2020 10:09:58.370] [Server thread/WARN] [net.minecraft.network.datasync.EntityDataManager/]: defineId called for: class its_meow.betteranimalsplus.common.entity.EntityGoat from class dev.itsmeow.betteranimalsplus.imdlib.entity.util.EntityTypeContainer
[28dic2020 10:09:58.465] [Server thread/WARN] [net.minecraft.network.datasync.EntityDataManager/]: defineId called for: class its_meow.betteranimalsplus.common.entity.EntityCoyote from class dev.itsmeow.betteranimalsplus.imdlib.entity.util.EntityTypeContainer
[28dic2020 10:09:58.498] [Server thread/WARN] [net.minecraft.network.datasync.EntityDataManager/]: defineId called for: class its_meow.betteranimalsplus.common.entity.EntitySquirrel from class dev.itsmeow.betteranimalsplus.imdlib.entity.util.EntityTypeContainer
[28dic2020 10:09:58.512] [Server thread/WARN] [net.minecraft.network.datasync.EntityDataManager/]: defineId called for: class its_meow.betteranimalsplus.common.entity.EntityTurkey from class dev.itsmeow.betteranimalsplus.imdlib.entity.util.EntityTypeContainer
[28dic2020 10:09:58.527] [Server thread/INFO] [net.minecraft.world.chunk.listener.LoggingChunkStatusListener/]: Time elapsed: 2694 ms
[28dic2020 10:09:58.529] [Server thread/INFO] [net.minecraft.server.dedicated.DedicatedServer/]: Done (3.121s)! For help, type "help"
[28dic2020 10:09:58.553] [Server thread/INFO] [com.maciej916.maessentials.common.util.LogUtils/]: maessentials Setup world
[28dic2020 10:09:58.555] [Server thread/INFO] [com.maciej916.maessentials.common.util.LogUtils/]: maessentials Mod is running on server
[28dic2020 10:09:58.557] [Server thread/INFO] [com.maciej916.maessentials.common.util.LogUtils/]: maessentials Loading data
[28dic2020 10:09:58.628] [Server thread/INFO] [com.maciej916.maessentials.common.util.LogUtils/]: maessentials Data loaded
[28dic2020 10:09:59.866] [Server thread/INFO] [tombstone/]: The list of contributors has been loaded successfully
[28dic2020 10:11:51.978] [Server thread/INFO] [net.minecraft.network.login.ServerLoginNetHandler/]: com.mojang.authlib.GameProfile@39d79faf[id=<null>,name=samu,properties={},legacy=false] (/26.18.128.117:53858) lost connection: Disconnected
[28dic2020 10:13:33.122] [Server thread/INFO] [net.minecraft.network.login.ServerLoginNetHandler/]: com.mojang.authlib.GameProfile@7de1e61e[id=<null>,name=samu,properties={},legacy=false] (/26.18.128.117:53863) lost connection: Disconnected
[28dic2020 10:14:06.321] [Server thread/INFO] [net.minecraft.network.login.ServerLoginNetHandler/]: com.mojang.authlib.GameProfile@79b5bc74[id=<null>,name=samu,properties={},legacy=false] (/26.18.128.117:53869) lost connection: Disconnected
[28dic2020 10:15:28.422] [Server thread/INFO] [net.minecraft.network.login.ServerLoginNetHandler/]: com.mojang.authlib.GameProfile@1a1bcda7[id=<null>,name=samu,properties={},legacy=false] (/26.18.128.117:53874) lost connection: Disconnected
[28dic2020 10:18:20.322] [Server thread/INFO] [net.minecraft.network.login.ServerLoginNetHandler/]: com.mojang.authlib.GameProfile@73e9e55b[id=<null>,name=samu,properties={},legacy=false] (/26.18.128.117:53882) lost connection: Disconnected
[28dic2020 10:20:00.022] [Server thread/INFO] [tombstone/]: All players have been successfully backed up
[28dic2020 10:20:07.271] [Server thread/INFO] [net.minecraft.network.login.ServerLoginNetHandler/]: com.mojang.authlib.GameProfile@60825d94[id=<null>,name=samu,properties={},legacy=false] (/26.18.128.117:53892) lost connection: Disconnected