how to block dhcp from my client to my router with a script?
You gave very little information, but from what I can see your client probably connects using a 2.4GHz AP/Bridge, and you have default forwarding on on your highsite.
I suggest disabling default forward on your 2.4GHz distribution interface, and make sure all Access List entries are also set to not have forwarding enabled.
k i will try it
if you have routeros handling your DHCP requests then set authoritative to yes and that will solve your rogue dhcp server problem.
i have all dhcp disable also in my router also in my ap
So you are running an all static network with no DHCP at all?
chain-forward
source ip - your ip subnet i.e. 192.168.0.0/24
protocol - udp
ports 67 & 68
action - drop
i had do it but not work 
to block dhcp server altogether use feature from dhcp-server, set it authoritative=yes
where i set it
if you are running dhc-server then you can use this option. it is one of dhcp-server settings.
Actually, the man does not use dhcp at all, this is how i see it.
If your clients are using wireless to connect to you, and you have wireless interface in routeros, then disable forwarding among clients. If your wireless interface is a separate box, look into it for “client isolation” or something similar. This will disable forwarding of dhcp requests among clients.
If you are not using dhcp at all, than why should this bother at all ? 
They’ll call you for proper address… ( they will do that even if they are overlapping their dhcp with your address space, of course.)
Jorj.
I have to block the dhcp because I have problems on the network
What kind of problems ? Be a little more specific…