I'm using Cisco Packet Tracer for Simulation and got error "ip address overlaps with..etc"

Solution 1:

Your addressing is indeed wrong :-(

First entry is correct, but second is fundamentally wrong. Prefix and mask is ok, but network and range is not. You cannot have a network .4 with a prefix of 27.

27 prefix says - 27 most significant bits of address specifies network. Rest of 32 bits is filled with 0. So last octet must be: xxx00000. When you entered your second ip address, router calculated network address for it (cleared last 5 bits) to be 192.168.1.0, which is the same as your first network, hence 'overlapping' error.

Solution 2:

Actually, you could have done it the other way: 192.168.1.0/27 and 192.168.1.32/30.