Visit the FreakTab forums, post a clear photo of your EP-68 PCB (both sides), and the community will link you directly to the exact firmware file you need.
Some users host backups on Google Drive , though these should be verified for safety before use. How to Flash the Firmware Rk3128 Mxq Ep 68 Firmware
If you still cannot find the exact firmware, consider using a and then manually replacing the boot.img and Wi-Fi kernel modules from a backup – but that's an advanced topic. Visit the FreakTab forums, post a clear photo