This happens when you haven't written down your image completely. For example, the last 4k block was not recorded.
When closing partitions, there is image validation. As a result, the following message is printed.

I got the same bug. I am writing a 4k block in an OTA partition, but for some reason the last block, which is less than 4k, is written in place of the first block at the beginning of the partition. That is, an overflow occurred. I don’t know, but maybe this is due to an incorrect partition table.