Boot camp failed to remove the partition. Now it’s labelled free space and I can’t remove it

Thank you for clearing that up.

Regardless, because this is a Partition and not a Volume ( Not the same thing ), to regain this empty space, the Entire Drive will need to the Reformatted.

This will remove the Partition left behind by the failed Bootcamp method to remove it.

It will also remove Everything for the computer.

You will be able to Restore from your TM Backup Drive

This method will WIPE ALL Data and there is No Recovery - Period.

>> Only works on Intel Based Apple Computer <<

To perform this action will require booting from a Bootable Installer. 

The Bootable Installer can Only be performed on an Apple Computer 

This will have to be performed from a Qualifying Computer to run the version of macOS to be made on the Bootable Installer. Example : Bootable Installer of Monterey would have to be done on a computer that Qualifies to run Monterey.

Notation: If the computer being used to perform this action is Too New or Too Old to qualify to run the version of macOS - this computer can not be used.

Alternative is, to gain access to a Qualifying Apple Computer from a family member, friend or associate.

Extra Special Notation regarding the Touch ID equipped Apple Computer.

About Startup Security Utility and Must Enable from Recovery Mode the ability to boot from External Drive Before Attempting 

1 - Shutdown computer and disconnect all external drive Except the newly created Bootable Installer.

2- Restart and immediately hold the OPTION key until the Startup Manager appears and choose the USB Drive. 

3 - It will present options >> Disk Utilities >> View >> View ALL attached Drives. 

4 - Choose the Upper Most Drive ( not the volumes indented and list below ).

5 - The drive normally is called Apple Media or Apple SSD - that is the drive to Erase and format as APFS with the GUID Partition Map. This applies to macOS 10.14 Mojave and above. 

6 - Once that is done >> backup out of Disk Utilities and choose install macOS. 

7 - Follow the prompts and it may automatically reboot several time. 

8 - Upon a final reboot - Setup Assist will present with the newer version of macOS.

Hello Cayde3672,

This page here can help provide some steps and info that may be able to help out with removing that Boot Camp partition: Remove Windows from your Mac using Boot Camp

1. Start up your Mac in macOS.

2. Back up all important data stored on your Windows partition before you remove Windows.

WARNING: When Windows is removed, the Windows partition—as well as all data stored in the partition—will be erased permanently.

3. Quit all open apps and log out any other users.

4. Open Boot Camp Assistant , then click Continue.

5. If the Select Tasks step appears, select “Remove Windows 10 or later version,” then click Continue.

6. Do one of the following:

•If your Mac has a single internal disk, click Restore.

•If your Mac has multiple internal disks, select the Windows disk, select “Restore disk to a single macOS partition,” then click Continue.

Cheers.

User wrote " Hello! I have a 2017 MacBook Pro running Monterey. Recently, I installed windows via boot camp, today I tried to remove the partition and it failed. I tried again through boot camp and the option to is gone. Only allows me to create a new boot camp partition. I went to disk utility and nothing…. Except, a free space partition which I am unable to remove.

Help!

A - This implies the user attempted to remove the Bootcamp created Partition manually and not from Within the Bootcamp Application itself ?

Am I reading this correctly ?

A - If yes, you may have to Wipe the Entire Drive and commence to reinstall the Operating system from scratch

Yes it would as Time Machine Backup does backup the Bootcamp Partition.

You would need to be very selective as to what is Restored.

Perhaps Only your User Account. Then and selectively to restore individual personal files

Back up your Mac with Time Machine - Apple Support (CA)

• To exclude items from your backup, open Time Machine preferences, click Options, then click the add (+) button to add an item to be excluded. To stop excluding an item, such as an external hard drive, select the item and click the remove (–) button.