diff --git a/netpfga/minip4/testdata/gen_testdata_nat64_500byte.py b/netpfga/minip4/testdata/gen_testdata_nat64_500byte.py
index 2055c03..c00b2c0 100755
--- a/netpfga/minip4/testdata/gen_testdata_nat64_500byte.py
+++ b/netpfga/minip4/testdata/gen_testdata_nat64_500byte.py
@@ -114,7 +114,7 @@ def test_nat64():
     p4 = 500 * "A"
     pkg4 = e4 / i4 / u4 / p4
 
-    applyPkt(pkt4, "nf2", pktCnt)
+    applyPkg(pkg4, "nf2", pkgCnt)
 
     e6 = e4
     i6 = IPv6(src = "2001:db8:42::a00:2a", dst = "2001:db8:42::42")
@@ -122,9 +122,9 @@ def test_nat64():
     p6 = p4
     pkg6 = e6 / i6 / u6 / p6
 
-    expPkt(pkt6,   'nf3')
+    expPkg(pkg6,   'nf3')
 
-    pktCnt += 1
+    pkgCnt += 1
 
     # From v6 to v4
     e6 = Ether(dst=MAC1, src=MAC2)
@@ -139,8 +139,8 @@ def test_nat64():
     p4 = p6
     pkg4 = e4 / i4 / u4 / p4
 
-    applyPkt(pkt6, "nf3", pktCnt)
-    expPkt(pkt4,   'nf2')
+    applyPkg(pkg6, "nf3", pkgCnt)
+    expPkg(pkg4,   'nf2')
 
 
 test_nat64()