Since you are using a struct the
ManagedBuffer inside the struc are nested encoded. Which means you need to add the length of the
ManagedBuffer before it.
Luckily there is a shortcut for that by using the
So your arguments would look like this:
"arguments": [ ["str:NFT 1"], ["str:www.mycoolnft.com/nft1.jpg"], [ ["nested:str:test1", "nested:str:test2"] ] ]
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