Hello, do you know if it is manipulated by software? You have to check the firmware that it originally has, if it is Chinese, global, if they have put a micloud baypass on it and they have only flashed the persist.img partition, if after all this it doesn't even take 4g, 5g, only 3g, you will have to look at it at the hardware level.Hello, Frankie, 38 Poco X 4 Pro, the latest Android, recognizes all SIM cards, except for the active SIM card, it does not ring, it does not ring, but it gives an antenna to Android 12. When I go to 3G, it rings, but it does not work. What is the solution? Thank you