Hi, in case you have two gateways with identical DIDs such issue may arise indeed, which is related to identifying the source of the calls. What you could do however is to fake an extra digit infront of each DID presented by the second gateway, with a manipulation made at the gateway config file level. Actually this occurs because with gateways you don't have Source identification settings as in Trunks. With 2 trunks of same sip server you would apply source identification on one of the fields which provide something unique such as an authentication number. If there was a source identification section in the inbound parameters of the gateways you could have filtered on the gateway host/port variable in one of the fields as INVIT|E from gw1 vs gw2 have different host. Thanks.