Hello Ujang,
This behavior is expected. The “Force a specific default lock screen and logon image” Group Policy is supported on Windows 11 Enterprise and Education, but not Windows 11 Pro. This explains why the same domain GPO works on your Enterprise devices but not on Pro.
For Windows 11 Pro, Microsoft documents managing the lock-screen image through the Personalization CSP instead, for example using Intune/MDM and the LockScreenImageUrl policy. The image can be provided through an HTTP/HTTPS URL or supported local/file location depending on the CSP setting.
Therefore, changing the AD GPO itself will not make this policy apply to Windows 11 Pro. If you must manage Windows 11 Pro devices, use an MDM/CSP-based deployment such as Microsoft Intune, or upgrade the devices to an edition that supports the lock-screen GPO.