Hello I made a mod with custom armor (flaming obsidian armor) and when I equip it in my server I get kicked for "Internal server error"

This is the log that I can find about my mod:

 

at net.minecraft.server.MinecraftServer.tick(MinecraftServer.java:668) [MinecraftServer.class:?]
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:526) [MinecraftServer.class:?]
at java.lang.Thread.run(Thread.java:748) [?:1.8.0_211]
Caused by: java.lang.NoSuchMethodError: net.minecraft.entity.player.InventoryPlayer.func_70440_f(I)Lnet/minecraft/item/ItemStack;
at mod.gttiqwt.emeraldobsidian.init.items.FlamingArmor.onArmorTick(FlamingArmor.java:37) ~[FlamingArmor.class:?]

idk how to put spoilers sorry for the long text..

how do I fix this? I think its because its rendering the armor on client side or something and I've had to fix this for an older mod but dont know how to. thanks

here's my class for the armor also: (The armor just extends "ArmorItem" basically and adds some potion effects when the full set it worn. works in singeplayer)

{
    public UpgradedArmor(IArmorMaterial materialIn, EquipmentSlotType slot, Properties builder)
    {
        super(materialIn, slot, builder);
    }
     @Override
        public void onArmorTick(ItemStack stack, World world, PlayerEntity player) {
            if(player.getItemStackFromSlot(EquipmentSlotType.HEAD).getItem() == ItemList.jewelled_emerald_helmet && 
                player.getItemStackFromSlot(EquipmentSlotType.CHEST).getItem() == ItemList.jewelled_emerald_chestplate && 
                player.getItemStackFromSlot(EquipmentSlotType.LEGS).getItem() == ItemList.jewelled_emerald_leggings && 
                player.getItemStackFromSlot(EquipmentSlotType.FEET).getItem() == ItemList.jewelled_emerald_boots) 
            {            
                    player.addPotionEffect(new EffectInstance(Effects.REGENERATION));
                    player.addPotionEffect(new EffectInstance(Effects.HERO_OF_THE_VILLAGE)); //instead of luck, better trades forever!
                    player.addPotionEffect(new EffectInstance(Effects.WATER_BREATHING));
                    player.addPotionEffect(new EffectInstance(Effects.HASTE));
            }
            if(player.getItemStackFromSlot(EquipmentSlotType.HEAD).getItem() == ItemList.flaming_obsidian_helmet && 
                    player.getItemStackFromSlot(EquipmentSlotType.CHEST).getItem() == ItemList.flaming_obsidian_chestplate && 
                    player.getItemStackFromSlot(EquipmentSlotType.LEGS).getItem() == ItemList.flaming_obsidian_leggings && 
                    player.getItemStackFromSlot(EquipmentSlotType.FEET).getItem() == ItemList.flaming_obsidian_boots)
                {
                        player.addPotionEffect(new EffectInstance(Effects.FIRE_RESISTANCE));
                        player.addPotionEffect(new EffectInstance(Effects.RESISTANCE));
                        player.addPotionEffect(new EffectInstance(Effects.STRENGTH)); //new
                }
        }
}

 and then registered like this in the main class:

ItemList.flaming_obsidian_helmet = new UpgradedArmor(ArmorMaterialList.flaming_obsidian, EquipmentSlotType.HEAD, new Item.Properties().group(itemTab)).setRegistryName(location("flaming_obsidian_helmet")),
						ItemList.flaming_obsidian_chestplate = new UpgradedArmor(ArmorMaterialList.flaming_obsidian, EquipmentSlotType.CHEST, new Item.Properties().group(itemTab)).setRegistryName(location("flaming_obsidian_chestplate")),
						ItemList.flaming_obsidian_leggings = new UpgradedArmor(ArmorMaterialList.flaming_obsidian, EquipmentSlotType.LEGS, new Item.Properties().group(itemTab)).setRegistryName(location("flaming_obsidian_leggings")),
						ItemList.flaming_obsidian_boots = new UpgradedArmor(ArmorMaterialList.flaming_obsidian, EquipmentSlotType.FEET, new Item.Properties().group(itemTab)).setRegistryName(location("flaming_obsidian_boots"))

 

heres some more info:

> [K[33;1m[07:12:53] [Server thread/WARN] [minecraft/NetworkSystem]: Failed to handle packet for / (server ip)
net.minecraft.util.ReportedException: Ticking player
at net.minecraft.entity.player.EntityPlayerMP.onUpdateEntity(EntityPlayerMP.java:459) ~[oq.class:?]
at net.minecraft.network.NetHandlerPlayServer.update(NetHandlerPlayServer.java:173) ~[pa.class:?]
at net.minecraftforge.fml.common.network.handshake.NetworkDispatcher$1.update(NetworkDispatcher.java:209) ~[NetworkDispatcher$1.class:?]
at net.minecraft.network.NetworkManager.processReceivedPackets(NetworkManager.java:285) ~[gw.class:?]
at net.minecraft.network.NetworkSystem.networkTick(NetworkSystem.java:180) [oz.class:?]
at net.minecraft.server.MinecraftServer.updateTimeLightAndEntities(MinecraftServer.java:790) [MinecraftServer.class:?]
at net.minecraft.server.dedicated.DedicatedServer.updateTimeLightAndEntities(DedicatedServer.java:397) [nz.class:?]

at net.minecraft.server.MinecraftServer.tick(MinecraftServer.java:668) [MinecraftServer.class:?]

at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:526) [MinecraftServer.class:?]
at java.lang.Thread.run(Thread.java:748) [?:1.8.0_211]
Caused by: java.lang.NoSuchMethodError: net.minecraft.entity.player.InventoryPlayer.func_70440_f(I)Lnet/minecraft/item/ItemStack;
at mod.gttiqwt.emeraldobsidian.init.items.FlamingArmor.onArmorTick(FlamingArmor.java:37) ~[FlamingArmor.class:?]
at net.minecraft.entity.player.InventoryPlayer.decrementAnimations(InventoryPlayer.java:371) ~[aec.class:?]
at net.minecraft.entity.player.EntityPlayer.onLivingUpdate(EntityPlayer.java:511) ~[aed.class:?]
at net.minecraft.entity.EntityLivingBase.onUpdate(EntityLivingBase.java:2179) ~[vp.class:?]
at net.minecraft.entity.player.EntityPlayer.onUpdate(EntityPlayer.java:234) ~[aed.class:?]
at net.minecraft.entity.player.EntityPlayerMP.onUpdateEntity(EntityPlayerMP.java:382) ~[oq.class:?]
... 9 more
[39;0m> [K[07:12:53] [Server thread/INFO] [Astral Sorcery]: [Astral Sorcery] Synchronizing baseline information to GttiqwT
> [K[07:12:53] [Server thread/INFO] [minecraft/NetHandlerPlayServer]: GttiqwT lost connection: Internal server error

 

1.14.4 is not supported in this forum. Please update to 1.15.2 or higher

bruh really. how am I supposed to get any support...

Just now, Mightydanp said:

1.14.4 is not supported in this forum. Please update to 1.15.2 or higher

 

"we dont support 1.12.2" now you dont suppoert 1.14. come on.

yes i understand I am updating my stuff to 1.16.3
you should to because most mods have updated to it