Good question. I don't know, but it does happen to some people some times.
You might want to use the hist.nostr.land service above that nostr:nprofile1qyfhwumn8ghj7mn9waejuat50phjummwv5qs6amnwvaz7tmwdaejumr0dsqzqxyst5996c36hqdf3w5cckpt6h6h7fgxc6uq3yzlckvatg9j9xcg4znv0k recommended in case it happens to you.