I am building a survival map, but I want to make a small part of the map strictly adventure mode. I have several command blocks hooked up to a 2-repeater pulsar, and once the chunk is loaded, all but two of these command blocks work fine. The two that do not work have the commands listed below:

/gamemode @a[m=0,r=2000] 2

/gamemode @a[m=1,r=2000] 2

I expected these to make it impossible for any player to be in a game mode other than Adventure.

Nothing actually happened. I have tried replacing the @a with @p, and it still does not work. I need to have a range on the command blocks so that when the chunk that they are in is loaded the do not change all player's game modes to Adventure.

The command blocks are directly powered by repeaters, so power should not be a problem