Why am I receiving text messages giving me an Apple ID code when I haven’t asked for one ?

Someone knows your Apple ID login but luckily you turned on your two-factor authentication hence you are receiving a code.

Simply change your Apple ID password to a stronger one. Change your Apple ID password - Apple Support

It could be somebody else has your Apple ID and password and is trying to sign in. That's how two factor authentication works.

Click on this link "If you think your Apple ID has been compromised" --> https://support.apple.com/HT204145

'Checklist: If you want to see if anyone else has access to your device or accounts' click here --> https://support.apple.com/HT212021

Security and your Apple ID - https://support.apple.com/HT201303

Contact Apple for help with Apple ID account security - https://support.apple.com/HT204169 "This article provides country-specific Apple Support contact information for customers seeking help with their Apple ID password or other security-related issues." Better for directly reporting an issue.