If you followed my root guide for Doogee X5 and now you need to get back to original state, you can get the needed files here.
Just use the Flash Tool as explained in the unroot guide and choose the right files from the V13 Firmware folder. Place the firmware folder inside the Flash Tool one, works better, don´t know why.
One of the things that made me return to rooted firmware was the fact that some apps were not working without the V14 OTA update, like the Paypal one.