The Stable update V188.8.131.52.QCRMIXM has been officially released for Redmi 9C (codename is angelica). Before updating, please make sure you have downloaded the exact ROM matching your Xiaomi phone/tablet. In Fastboot mode, you can check model code by typing
fastboot getvar product in cmd/shell.
The firmware files posted here are all official Xiaomi ROM, xiaomiROM.com do not own and never modified those firmwares，you will always download the file from Xiaomi server.
You may interest in those contents: Redmi 9C ROM Topics Xiaomi Devices Index
Download Redmi 9c (angelica) Global MIUI 12 V184.108.40.206.QCRMIXM Recovery ROM with Android 10.0. Firmware size is 1.9 GB.
Download Redmi 9c (angelica) Global MIUI 12 V220.127.116.11.QCRMIXM Fastboot ROM with Android 10.0. Firmware size is 4.5 GB.