Download Android 7.1 stock firmware for CSA95 TV Stick from here and here. Download previous firmware from here. Download Amlogic USB Burning Tool v2.1.6 from here or download Amlogic Burn_Card_Maker v2.0.2 from here.
Archive: How to flash CSA95 Tool+ Steps
Model: CSA95 TV Stick
Image file size: 557 MB
Platform: Amlogic S912
Inside archive: firmware + Instructions + Amlogic S912 burnning tool (setup_v18.104.22.168_build7)
Caution: Please do not update firmware unless you know what you are doing, you really want it or it is absolutely necessary. Firmware updates may occasionally have bad results, like bricking your device, temporarily or permanently. The firmware update process is done entirely at your own risk. Before attempting to update the firmware, back up your data.