Any VPN software installed/uninstalled on the system recently? Anyway, please try the RasMan fixes on this page.
Run DISM and SFC: https://support.microsoft.com/en-us/topic/use-the-system-file-checker-tool-to-repair-missing-or-corrupted-system-files-79aa86cb-ca52-166a-92a3-966e85d4094e
If nothing helps, you may run a ProcMon trace to capture the RasMan service start events. Or simply repair your Windows 11 installation by downloading the Enterprise ISO.