Testing in-app purchases

I need to test my app's in-app purchases and I am having a very difficult time with it.

I created a "Sandbox" account in App Store connect. Doing so was very frustrating. It told me multiple times that my password was "too simple", without ever explaining what the password rules are. Then it emailed me something so I could "validate" the account. Luckily I used an actual email address that I can receive mail on. I was expecting I could use any fake address since this is a Sandbox account.

After that I started an iOS simulator and tried to log in. It immediately asked me to turn on two-factor authentication. I declined, and then it just said "User name or password is incorrect". I tried a couple more times, then I went back and actually turned on the two factor auth. But that didn't solve the problem. I still cannot log in.

Can someone explain what I'm doing wrong here?

Testing in-app purchases
 
 
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