Hey, Janicemaye, you have solved the issue, right? But I still want to share some tips here, not just for you, but for the people who have the similar experiences. Now let's start.
Method 1. Reset macOS Password Using Recovery Mode.
This process is very straightforward and easy. You don’t need anything. No, bootable USB for macOS and no macOS DVD. Apple includes a Utility to reset an administrator’s password on every install Recovery HD partition. To use the Reset Password app, you’ll need to start your Mac using either the install DVD or the Recovery HD.
Step 1. First, Restart your computer and then press and hold Command+R until the Apple logo should appear. It means that you boot your device in Recovery Mode.
Step 2: On the welcome window choose the language then hit at Continue arrow button.
Step 3: A new window will be shown to you and navigate to Utilities Tab> Terminal.
Step 4: When you clicked on Terminal, start typing the below command.
Step 5: Choose the username then click Next.
Step 6: Type New Password with an appropriate hint that should not forget next time. Keep in mind that verify the password. It means you should enter the password for two times. Now click Next.
Step 7: Your user account password has been reset. Now you can reboot your computer to sign in with the new password. Click Restart.
Step 8: Type your new password then hit Enter.
Method 2. Create New Admin Account to Reset the Old One
Step 1: Restart your Mac computer then press and hold on the Command+S from the keyboard.
Step 2: You’ll be promoted to a black colored screen with white color text. So type the following commands after one another.
Step 3: Once your system is restarted, don’t touch any key then let it boot normally.
Step 4: When the system boots, you will see the installation process when you setup MacOS for the first time.
Step 5: Create a new user account.
Step 6: Once you login to your new account, navigate to Apple logo> Preferences> Users & Groups.
Step 7: Click the “Lock” icon then enter your “Username” and “Password”.
Step 8: Choose the old user then click on “Reset Password“.
Step 9: Type the new password and verify it. If you would like to enter a hint just type and click “Change Password”. log out of your account and navigate to your old account with the new password you have created in step 9.