Hi @Nur Hossain
Yes, you should increase the lease time and also try setting the static DHCP option for the connected clients and see if this does not disconnect the connection.
DHCP Lease Time is the amount of time in minutes or seconds a network device can use an IP Address in a network. The IP Address is reserved for that device until the reservation expires.
The default lease time for the DHCP server is 24 hours. When setting the lease time on your DHCP server, consider your goals, usage patterns of your site, and service arrangements for your DHCP server.
Hope this resolves your Query!!
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