Download Vernee Apollo X official stock firmware from the link here, and follow the provided flashing instructions to learn how to flash the stock rom.
This firmware is an sdcard update package. So you basically need just an sdcard and your device to flash the firmware.
If you notice that any of the links provided below is broken or doesn’t work, please post in comments section so we fix and update it ASAP.
File Name: full_k15tb_a-ota-1490679079.zip
Size: 893 MB
Release Date: 20170425
Firmware – Download
How to flash
1. Download the ROM file from above link and copy to your device internal storage (sdcard).
2. Launch “Setting” -> “About Phone”->“wireless update”, then click the icon at the top right corner, and choose “Local updates”;
3. Click into “internal storage”, find the ROM file and choose it;
4. Click “install now” and choose “OK” from the popup to commence update.
5. Wait patiently for the flashing process to commence and complete. During this peroid, your device will reboot. That’s all.