mobiles iPhone clients

How do I prevent clients from the broadcast via mobile phones
For example, customers who use mobiles iPhone
Can after login in hotspot that is sharing with their friends online
How do I block it and make the login page show them and can not get online, but by using a user name and password last
For your information I’ve put this
Rulr script is useless and I am slowly in the network after being placed

/ip firewall mangle add action=change-ttl new-ttl=set:1 chain=forward out-interface=ether3 comment=“Block Client NAT/Router / Suppor”

???

That’s correct approach. But note that client can set ttl as he wants again.