That’s what the article is about

Same

You need to get L1 keys somehow, and as far as I know, there are no guides on how to do this. The L1 keys are protected using a Trusted Execution Environment (TEE), like the TPM on PCs (Windows) and ARM TrustZone for mobile devices, making it very hard to crack them. Although this has happened before, now they should’ve patched the exploit, and if you want to get L1 keys you will have to reverse engineer the chips and find your own.