Login failed AppSheet Toolbox Extension from my AppSheet account

[Cesarrincon1a]

Hi @Stefan_Quartemont, I have registered on the platform https://appsheettraining.com/

But when I try to access AppSheet Toolbox from my AppSheet account with the access data registered on their platform it tells me that:
"Login failed.
We didn’t find an account with those login credentials"

Please help me
Thank you.

César