Sign-in problems with your Yahoo account:

If you cannot sign in to your account or the account appears locked, follow the instructions in the following link:

https://help.yahoo.com/kb/yahoo-account/unable-sign-account-sln2051.html

The Yahoo Help Center:

For any other information about Yahoo services you can follow the link below:

https://help.yahoo.com/kb/yahoo–account

Yahoo is reported to be based in the US. and is therefore subject to local foreign law.