I have to repost my question because the answer is not related to my question in my previous post.

https://ttlc.intuit.com/community/taxes/discussion/where-to-claim-bad-investment-write-off/00/298456...

I have some investments on notes issued by an online platform. One of the notes got defaulted, and the underlying borrower went bankrupt. The platform sent email to investors, saying they decided to write down 100% of the note value, because they don't think there would be any recovery value of the note.

In this case, can I claim this as capital loss? However, the online platform didn't send 1099-B for this defaulted note, how should I claim it in TT?