[eesh]

pawn Код:

new old[256],yes[MAX_PLAYERS][256];
GetPlayer2DZone(playerid,old,sizeof(old));
if(!strcmp(old, yes[playerid], true)) return 1;
format(yes[playerid],sizeof(yes[playerid]),"%s",old);
GameTextForPlayer(playerid,yes[playerid],2000,1);

the way you did yes = old might be the culprit.