[Finn]

You need to learn to use strcmp.

This is wrong:
if(strcmp("/rules", cmdtext, true, 10) == 0)

The number 10 you have in the function has to be the amount of characters the string (in this case "/rules") has. So, as you can see the number is wrong, because "/rules" has 6 characters.

You need to use:
if(strcmp("/rules", cmdtext, true, 6) == 0)

or:
if(strcmp("/rules", cmdtext, true) == 0)

strcmp in SA-MP wiki