Hello,
On TestNet, I created an SFT ( Asset - PUKR-30R2 | Klever Explorer ), and when I try to add the metadata, I’m getting the error “AssetTypeInvalid” ( Transaction - fe68a...390b5 | Klever Explorer ).
I’m not sure if the problem is that once the SFT is created, the metadata can no longer be modified, or if the metadata inclusion process doesn’t support SFTs. In either case, the token is available on the metadata modification screen.
Where could the problem lie?
Hello @Jose_Luis_Latas the @Blockchain team is checking and we’ll circle back to you soon.
It looks like the issue is related to where the metadata is being applied.
Please check whether you’re trying to add metadata directly to the main SFT collection (PUKR-30R2) instead of to a specific SFT item, such as PUKR-30R2/1.
For SFTs, metadata must be attached at the item level, not to the parent collection.
If the transaction is targeting only the base collection, the network will return an AssetTypeInvalid error.
Additionally, the metadata structure you used looks a bit unusual. It seems like it may have been parsed from a smart-contract call. Even so, it should work as long as the metadata is submitted to the correct item-level collection.
Could you verify which collection you attempted to update and try submitting the metadata to a specific item?
Please let us know the result so we can continue supporting you.
Perfect… I’m learning by doing tests and I had misunderstood how SFTs work. The way you’ve explained it reduces my workload considerably.
With what you’ve told me, I’ll continue to move forward, so thank you very much, and I’ll keep you updated.
Thanks again 
Perfect.
I’ve managed to read the metadata from one of the SFT collections using Python.