How do I log into Origin with a child account?

I recently bought Sims 4. I wanted to install it on my laptop, but since I forgot the charging cable my battery ran out. So I installed the game on my dad's laptop. I also created a child account for me there.

But now I want to play the game on my laptop. Since I have the charging cable again. However, the registration does not work. Neither on the website nor with the origin app is working.

Do I have to do anything special to sign up for a child account on Origin? And what about this origin error report? Would it be better to delete it? Re-installing the app didn't bring anything. Origin always tells me that my ID would not be available (I'm sure that I entered the ID correctly and I'm no longer logged in to origin on my father's laptop) . Only my laptop works smoothly there don't want to… Hope that was understandable. I appreciate quick answers.

Many topics.

I don't know a child account, only a limited account. You set everything you want and then activate the restricted account. This works with the computer's administrative rights.
I don't think games are written to the cloud. There are various instructions on how to save it.

Then I understood:

You have created an account with Origin.
Then you have logged into your father's computer with the Origin client.
Now you want to play SIMS4 on your laptop.
You actually get an email when you have successfully registered. I think I can remember that you log in there with your kick name.

If in doubt, you can create a new account and enter the data straight away in a password manager (e.g. Enpass).

Then you simply have fewer problems.