Glass cone piece

Selena

Hey girls, I recently purchased a bong with a glass cone piece. I usually use the ordinary cone piece. But after a few uses I’ve noticed the inside has either like melted from the heat or honestly I don’t know what its just like the actually hole has gone bigger 🤦🏽‍♀️🤦🏽‍♀️ so when I pack it and smoke it all my bud literally falls to the bottom and it’s like a whistling sound! Does anyone know what can prevent this for future glass pieces ?