xSIID chip writing, but not saving data?

[Pilgrimsmaster]

@reelnichole

2 months ago […] fully healed now, visible under the skin

That all sounds good

What size is the file you are trying to save?

Less than 1k?

Have you tried just a small text file / url etc?

So what happened with the 2k memory on the xSIID?

TL;DR - The first batch of xSIID made December 2019 were formatted to try to use all 2k of memory across two 1k memory sectors for NFC applications, but the NFC stacks built into Android and iOS phones don’t know how to properly read multiple memory sectors in NFC Type 2 chips. Future batches are formatted to only use the first memory sector which is 1k for NFC applications. The remaining 1k is still readable and writable by phones, but only with a custom smartphone app that can directly address…

Have you tried another App?
Like NFC tools, BioCom?