Command block don't work like they used to, because a repeating, always-on command block can be used to change commands in real time.
But in version 1.21.30 when you type say 1 on a repeating command block, it will execute once you change the command, it will no longer execute say 1, but will stop running unless you manually place a red stone block to refresh the command block to execute your latest command again.
So how do I fix it?
It's really sudden for someone I'm working on a map for!
Duplicate of MCPE-185944