"Option 129 Missing" has nothing to do with your power injector, assuming it is functioning correctly... It relates to a DHCP server configuration issue, static assignment missing for the phone, or a VLAN issue. The phone is basically saying "I am connected to the network, but the DHCP server on the VLAN is not giving me the information I need to find the phone system" so it either needs to be manually assigned (VLAN ID or ICP address) or the port it's connected to is not configured correctly.