A command block placed after the release of 1.20 will not run any commands even if activated by redstone or set to "Always Active".
Comments 2
Cleaning up old tickets: This ticket had been set to 'Awaiting Response', but has not received a response from the reporter (~3 months+) so is being closed as Incomplete. If you feel this is still a valid issue then please comment, or create a new ticket following the Issue Guidelines which includes steps to reproduce the problem.
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Have you checked whether you have the commandblocksenabled gamerule turned off?