The samples here are not working

[SoftwareMechanic]

In the beginning I thought it was just an issue with the uploader error, here what I face when I try to run createNft sample

code: "ERROR_MALFORMED_TOKEN", message: "API Key is malformed or failed to parse.

(I had to put "NEXT_PUBLIC_" in front of environment variables to avoid other errors).

but even commenting the uploading part and hardcoding a url with the asset metadata give me an error:

Error: Simulation failed. 
Message: Transaction simulation failed: Blockhash not found. 

considering I have to switch from metaplex-foundation/js to a new approach, what shoud I do now? is correct to start from this examples?