## Algorand Studio: Opt In – Address Seems to Be Malformed

It seems the problem is that you didn’t define Alice’s account in the ’ “accounts”: [ ], ’ part of 1.opt_in.json. According to the README.md of the Github [here](https://github.com/ObsidianLabs/AlgorandStudio#transaction-template), you need to define the addresses involved in the transaction.

**Disclaimer:** I haven’t used this software.