The latest account security feature is called two factor authentication and is used by practically everyone from Apple to Google to bank accounts.
Part of two factor authentication’s tight security is the reset process called account recovery which is an automated process which can take just a couple days or longer depending on multiple factors. How to use account recovery when you can’t reset your Apple ID password - Apple Support
As you have learned account recovery is a two phase process once started. Phase 1 is the evaluation period, usually 24-48 hours but can be longer or shorter. This phase says Apple is evaluating your info and you’ll get an update after the posted time is over (people mistakenly think it means they’ll be able to reset the password immediately after this first phase.)
Once phase 1 is done it enters phase 2 where https://iforgot.apple.com/ will give you the final amount of days (can be weeks) you’ll wait. On that final day you’ll get a text/email, follow that text/email immediately.