Unable to register Item texture can someone help?

So I am currently coding in a item and can’t get its texture to properly connect. Here is my code:

package assets.testmod.textures.items;

import com.shadowmaster.testmod.reference.Reference;

import net.minecraft.item.Item;

import net.minecraft.ItemStack; 
import net.minecraftforge.fml.relauncher.Side; 
import net.minecraftforge.fml.relauncher.SideOnly;

public class ItemSTM extends Item{
     public ItemSTM(){
           super();

     }

     @Override

     public String getUnlocalizedName(){
           return String.format(“item.%s%s”, Reference.MOD_ID.toLowerCase() + “:”, getUnwrappedUnlocalizedName(super.getUnlocalizedName()));

     }
 

     @Override

     public String getUnlocalizedName(ItemStack itemStack){
           return String.format(“item.%s%s”, Reference.MOD_ID.toLowerCase() + “:”, getUnwrappedUnlocalizedName(super.getUnlocalizedName()));

     }
 

     @Override

     @SideOnly(Side.CLIENT)

      public void registerIcons(IIconRegister iconRegister){
            itemIcon = iconRegister.registerIcon(this.getUnlocalizedName().substring(getUnlocalizedName().indexOf(“.”) + 1);
 

\* This is the piece having the issue but I can’t figure out why or how to fix it *\

      }

     protected String getUnwrappedUnlocalizedName(String unlocalizedName){
          return unlocalizedName.substring(unlocalizedName.indexOf(“.”) + 1);

     }

}