Please clarify the below queries :
On how many devices did you observe the issue.
You have mentioned the issue happened only twice. When you try to program the new data in those locations were you able to read the correct data.
thank you for the reply. We produced 400 devices and each of them has one flash chip. The data were written one month ago and when we checked them(hy just reading test)the issue happend. 2 devices got the problem. We reprogramed the locations and the data were read correct again. We tried really hard to test the chip but the issue never happened again. It's a mystery to us now.