HELP! Razer Mamba Chroma Optical problem

Hello, currently i bought Razer Firefly V2 mat and i use it for Razer mamba chroma mouse, but i got problem with the optical sensor. I decided to calibrate the mat using Razer synapse 2, but after i calibrated i still got problem with the optical sensor.. its feel like the sensor not smooth or something i cant describe how it feels. i tried to change the mat use the old one that made from "synthetic fabrics" and everything goes well. Do you guys have an idea whats happening with the mouse? i tried clean the optical with cotton bud + alcohol too