Occsionally, there may be a “stop job” in progress which might give the impression of a stalled shutdown. Hitting the Esc key should usually reveal whether or not this is the case.
A “stop job” may be called for a number of reasons, and can sometimes take up to 1.5 minutes to complete. Forcing a hard shutdown or reboot only means that the stop job isn’t allowed to complete, in which case it must run again at the next shutdown.
If this is actually the case, then patience is a distinct virtue.
Information only:
Every hard shutdown/reset can potentially damage your system. Many are unaware that there is a safer method to shut down a frozen system using REISUB/REISUO: