Interfaces not showing in "list resources"

Hi.

i'm trying to add a Dell Sonicwall FW, but the problem is when i get to the part to choose wich resources to monitor, i cannot get any interface.

Like this:

I don't have any problems with other nodes, even other FWs from the same brand, it only happens with this one, i checked using other monitoring tools, and works fine, i evend did a SNMPWALK from the CLI in the Orion Server and i get the right info.

iso.3.6.1.2.1.2.2.1.2.1 = STRING: "X0 (LAN)"

iso.3.6.1.2.1.2.2.1.2.2 = STRING: "X1 (WAN)"

iso.3.6.1.2.1.2.2.1.2.3 = STRING: "X2 (WAN)"

iso.3.6.1.2.1.2.2.1.2.4 = STRING: "X3 (Unassigned)"

iso.3.6.1.2.1.2.2.1.2.5 = STRING: "X4 (Unassigned)"

iso.3.6.1.2.1.2.2.1.2.6 = STRING: "X5 (HA-Link)"

iso.3.6.1.2.1.2.2.1.2.7 = STRING: "U0 (Unassigned)"

iso.3.6.1.2.1.2.2.1.2.8 = STRING: "U1 (Unassigned)"

¿How can i troubleshoot this? i tried to delete the node, re add it, reboot the server, etc. and nothing worked.

Thanks in advance.