[Relaxing]

I haven't tried if this works but seems 10 times better than
register_clcmd( "say /respawn", "CTrespawn" )
register_clcmd( "say /respawn", "TTrespawn" )

Spoiler

#include <amxmodx> 
#include <hamsandwich>

public plugin_init(){
    register_event("DeathMsg", "xDeathMsg", "a")
} 

public client_putinserver(id){
    set_task(5.0, "putinserver", 444);
}

public client_disconnect(id){
    if (task_exists(444)){
        remove_task(444);
    }
    
    if (task_exists(id)){
        remove_task(id);
    }
}

public xDeathMsg(){
    new Victim = read_data(2);
    set_task(1.0, "check_spawn", Victim);
}

public putinserver(id){
    id -= 444;
    new team = get_user_team(id);
    if (team == 1 || team == 2){
        check_spawn(id);
    }
}

public check_spawn(id){
    new team = get_user_team(id);
    if (team == 1 || team == 2 && !is_user_alive(id)){
        ExecuteHamB(Ham_CS_RoundRespawn, id);
    }
}