diff --git a/p4app/controller.py b/p4app/controller.py
index 1231284..a5ac4f1 100644
--- a/p4app/controller.py
+++ b/p4app/controller.py
@@ -246,12 +246,10 @@ class L2Controller(object):
 
         # S=1 -> solicitated
         i2 = ICMPv6ND_NA(S=1, R=0, tgt=src_addr)
-
-        # Force scapy to recalculate ??
-        i2.chksum = None
-
         i3 = ICMPv6NDOptDstLLAddr(lladdr=src_mac)
 
+        # Force scapy to recalculate ??
+        i.chksum = None
 
         answer = e / i / i2 / i3
         self.send_pkg(answer)