The honest answer first: nobody can bypass a modern phone's lock without erasing it. That is the point of the lock. Anyone offering to unlock it while keeping your data is either guessing your PIN or selling something that does not work.
What you can do is get the phone working again, and get your data back if it was backed up.
Before you erase anything, try to remember
- Try the PINs you use elsewhere: an old SIM PIN, MoMo PIN (if you reuse it), birth years.
- Patterns are often the shape of a letter or your initial.
- Wait out each lockout period calmly. Most phones allow more attempts over time.
- Samsung phones signed in to a Samsung account with Remote Unlock turned on can be unlocked at smartthingsfind.samsung.com without erasing. Check this first.
Android: erase it and start again
- On another phone or computer, go to google.com/android/find and sign in with the Google account on the phone.
- Choose the phone, then Factory reset device.
- When the phone restarts, it will ask for the Google account that was on it. This is Factory Reset Protection, and it stops thieves using stolen phones. You must know that email address and password.
- Sign in, and choose to restore from your Google backup.
If you cannot reach the phone online, you can also reset from recovery mode (usually Power and Volume Up while the phone is off). The Google account step still applies.
If you do not know the Google account password, recover it first at accounts.google.com, from another device. See recovering a Google account.
iPhone: erase it and restore
- After enough wrong attempts, an iPhone on iOS 15.2 or later shows Forgot passcode? or Erase iPhone on the lock screen. Tap it and enter your Apple Account password.
- Otherwise, connect it to a computer with iTunes or Finder, put it in recovery mode, and choose Restore.
- Sign in with your Apple Account when it restarts. Activation Lock requires it.
- Restore from your iCloud backup.
What you get back
Whatever was backed up: Google or iCloud contacts, photos in Google Photos or iCloud Photos, WhatsApp chats if WhatsApp backup was on. What was only on the phone is gone.
If you bought the phone second-hand and it is locked to someone else's account
Only the previous owner can remove it, by signing in or removing the phone from their account. If they will not, the phone is either stolen or will stay unusable. See buying a used phone.
Setting it up so this does not happen again
- Use a PIN you will not forget but others cannot guess, and add a fingerprint or face unlock so you type it less often and forget it less.
- Write your Google or Apple Account email and password somewhere safe at home.
- Keep backups on. It turns a forgotten PIN into an inconvenience rather than a loss.