Hello guys, I'm sorry for the question but ... I recently blocked the bootloader by fastboot (to get the rom for android 9 but, I didn't know I didn't need it) Now I want to unlock it again, but I can't because the unlocking application says an unknown error is occurring and the oem unlock option is not active (it appears, but in a gray tone) someone has been through this and knows how to solve it, thanks:dedos cruzados:
First of all, are you sure you have a ZD553KL/ZB553KL? Because as far as I know, there is NO LEGAL WAY TO RELOCK THE BOOTLOADER. Even if you did in an unofficial way, it's unadvisable.
If you just needed the latest ANDROID 9 BETA ROM. You can do a manual update even if your bootloader is unlocked. A MANUAL UPDATE WILL STILL WORK REGARDLESS OF BOOTLOADER STATUS.
Just download the rom from their site and flash it manually on a stock recovery