You should ask the vendor for the source code to build the 'firmware'.
Then YOU will need to migrate this v17.0 LEDE basis to the latest master OpenWRT code.
The mt7621 platform is relatively popular, and has quite a few devices already available under OpenWRT master.
But as noted, this does NOT mean that YOUR device has support. YOU will need to add support for YOUR device if YOU care to have the latest version.
The way to add support would be to create a Device Tree file (.dts) that represents the various hardware/software components for the device. That should allow you to build a bootable image.
You'd want to access the bootloader (this is your problem to solve), and load the bootable image into memory then boot from it. Hopefully that gives you a working device.
If it all works, then you can go about flashing that image into the non-volatile storage (NAND/NOR/eMMC/whatever) and that would be 'job done'...
If it doesn't work... well... that's a problem... you'd want to fix it...
@frollic@bevanweiss what I tried to say if the backup that I did for the bootloader , factory and the firmware is it is not enough using the cat /dev/mtd commands?
By the way a few minutes ago I contact my supplier and he said that he's going to send me the search code , as soon as he sender it i will post it here.
You will need to learn about how to compile the linux kernel, how to write a Device Tree for a new device. How to reverse engineer unknown hardware and potentially software interfaces.
You currently haven't shown much in the way of understanding of this.
So you will either need to put in some serious work to get your understanding up to speed.
Or just give up, and live with the software version contained within the firmware binaries the vendor has provided you.
Do NOT post it here.
You could create a github, and put it into your github, and put a link here.
But we are almost certainly not going to look into it.
You really missed the part earlier about YOU WILL NEED TO DO THE WORK.