Robx A2024 Laser Hair Removal Device Head Developed Internal Stain

I recently purchased a Robx A2024 laser hair removal device directly from the brand's official website. As shown in the attached photos, a distinct stain or mark has developed on the inside of the device head. I have used the device strictly in accordance with the user manual instructions and am only on my 6th treatment session. I have not misused the product or engaged in any improper handling that could damage the attachment.

Despite carefully cleaning the outer surface, the stain does not come off, confirming that the defect is located on the interior of the glass component. Discovering this flaw on a newly purchased device is extremely disappointing. Because this issue is clearly not the result of user error, I demand that the device head be replaced free of charge under warranty.

I request a prompt resolution to this matter so I can continue my treatments safely without further delay.