Bootloader memory corruption

Hello,

We have a number of devices that have stopped booting up, after power cycle we think.

When we investigate the memory holding the rom image we can see that it is corrupt/overwritten.

We use a flash memory of type S29GL064N. Our bootloader span over a sector ( 5000 0000 - 5001 1C4B).

We can see that often it is at the exact border (5000FFFF) to next sector that it is corrupted/over written with FF’s, but sometimes above.

So we do not use the top or bottom sector. As I understand a hardware pin is protecting first and last sector but since we do not use them we are not helped of that. My question is, what is needed to do ensure that the boot sector is secure/write protected. Is there any configuration? Does the fact that we go over one sector affects things?

Regards

Are you using Digi product?