I posted below but after completing the lesson this IS THE CORRECT ANSWER. Father down in lesson it addresses this exact issue. I and the OP both somehow started the transaction and something when wrong. SO it appears we we're both "stuck" mid transaction and not able to execute the query. I was only able to "fix" the issue via dropping the tables and starting over but that doesn't HELP the actual issue or help us understand what was going on. ROLLBACK is the correct method to fix this issue and future issues with this error.