Hi Rijaluddin,
Please follow this post: How to Connect to a PLC with an Unknown IP Address - Share Info & Ideas - B&R Community (br-automation.com)
In order to “see” the PLC you must have activated the SNMP parameter to ON on ETHERNET configuration. If you don’t know your IP address then you must send your PLC to BOOT state. As it says in the post:
Imagine you get your hands on a Compact-S or C-Panel PLC. You turn it on, eager to transfer the project you’ve been working on. You plug in your Ethernet cable, open up Automation Studio, try to search for it…and nothing shows up. Whoever used it last must have deactivated SNMP, and you don’t know the IP Address!
Fortunately, there’s a way to make your PLC discoverable again: put it into BOOT mode.