How long depends upon if she has even taken the steps to get it unlocked and the type or reason for the account ot have been locked.
The support article If your Apple Account is locked, not active, or disabled - Apple Support outlines reasons for an account to be disabled/locked/not-active:
● If a message says 'Your Media & Purchases account has been disabled' - Apple Support or "You cannot login because your account has been locked”you might be able to request reactivation by tapping Continue right from the alert, if available. If that does not work, Apple provides a link for this specific issue. Tap or click here and choose a self-help or contact method ➞ https://getsupport.apple.com/?caller=kbase&PGF=PGF63005&category_id=SC0245&symptom_id=23362 .
● If your account has been disabled for “security reasons” the solution is to reset your password as outlined in this document: If you forgot your Apple Account password - Apple Support
If you find you can’t sign in, reset your password, or receive verification codes, you can request account recovery (read this support article: How to use account recovery when you can’t reset your Apple Account password - Apple Support ) to regain access to your account. More detail in —> Activation Lockout Issues - Apple Community For additional assistance from Apple, go to: Contact Apple Support - Apple Support and try to connect with live support.
● If your account says “Account [is] locked”, or it is inactive, you might be able to request access to your account by tapping Request Access right from the alert, or by using this link —> https://iforgot.apple.com/unlock
If that does not work, this link (versus one taking you to the general support page) is the most direct way to get to the people helping you with this —> https://getsupport.apple.com/?PGF=PGF63005&category_id=SC0245&symptom_id=23626
A telephone number may be provided at the bottom of this support article --> Contact Apple Support - Apple Support
● Additional reasons (e.g., “This account is locked and can't be used “):
According to various posts, Apple may permanently lock accounts for other reasons (very broadly outlined in section VII-B of Legal - iCloud - Apple ). That may be the case here if none of the previous reasons apply to you. If it isn’t apparent, contact Apple and ask if that is the situation, but don’t expect them to tell you why. You, or somebody who has managed to get access to your account, are likely doing something Apple is interpreting as account misuse. You will have to see if your activities could be construed—rightly or wrongly—as meeting any of Apple's conditions in the legal article. You will need to create a new account and stop doing things the way you have been that may have caused the other account to be locked.
In this situation you may be able to still use your equipment with a new account or even no account at all. Apple can completely reset a device if a person can provide sufficient evidence of valid ownership. Check the requirements and steps at: Activation Lock support request - https://al-support.apple.com/#/additional-support Apple says, "Proof of ownership documentation is required," but does not detail what currently constitutes proof other than it “must include the product serial number, IMEI or MEID.” Apple may typically require the original receipt* issued by Apple or an Apple Authorized Reseller. If Apple resets the device this will give you access to the device but won't restore access to the account used to lock it. There is nothing that can be done to expedite an Activation Lock request.
*Apple recommends you "Keep your receipt after you buy an Apple device" --> https://support.apple.com/102264
● If you deactivated your account, see the section about "Can I reactivate my account?" —> https://support.apple.com/102268
