[Seven_of_Nine]

You can't use SendClientMessage to send formatted messages.
Add this to the top of your script:

pawn Код:

#define SendFormattedMessage(%0,%1,%2,%3) \
new text[128]; \
format(text,sizeof(text),%2,%3); \
SendClientMessage(%0,%1,text)

And use like:

pawn Код:

SendFormattedMessage(playerid,red,"You have set your head text message to %s",params);

Untested, if not works then:

pawn Код:

new text[128];
format(text,sizeof(text),"You have set your head text message to %s",params);
SendClientMessage(playerid,red,text);

Good luck with your code.