diff --git a/pkg/compiler/native_test.go b/pkg/compiler/native_test.go
index 49460401b..a486e49c0 100644
--- a/pkg/compiler/native_test.go
+++ b/pkg/compiler/native_test.go
@@ -282,7 +282,7 @@ func getMethod(t *testing.T, ctr interop.ContractMD, name string, params []strin
 	}
 
 	md, ok := ctr.GetMethod(name, paramLen)
-	require.True(t, ok)
+	require.True(t, ok, ctr.Manifest.Name, name, paramLen)
 	return md
 }
 
diff --git a/pkg/core/interop/context.go b/pkg/core/interop/context.go
index 4a734ad42..0c7419284 100644
--- a/pkg/core/interop/context.go
+++ b/pkg/core/interop/context.go
@@ -207,7 +207,7 @@ func (c *ContractMD) AddMethod(md *MethodAndPrice, desc *manifest.Method) {
 	index := sort.Search(len(c.Manifest.ABI.Methods), func(i int) bool {
 		md := c.Manifest.ABI.Methods[i]
 		if md.Name != desc.Name {
-			return md.Name >= desc.Name
+			return strings.ToLower(md.Name) >= strings.ToLower(desc.Name)
 		}
 		return len(md.Parameters) > len(desc.Parameters)
 	})
@@ -236,7 +236,7 @@ func (c *ContractMD) GetMethodByOffset(offset int) (MethodAndPrice, bool) {
 func (c *ContractMD) GetMethod(name string, paramCount int) (MethodAndPrice, bool) {
 	index := sort.Search(len(c.Methods), func(i int) bool {
 		md := c.Methods[i]
-		res := strings.Compare(name, md.MD.Name)
+		res := strings.Compare(strings.ToLower(name), strings.ToLower(md.MD.Name))
 		switch res {
 		case -1, 1:
 			return res == -1
diff --git a/pkg/core/interop_system_core_test.go b/pkg/core/interop_system_core_test.go
index 7beff0888..e0211922f 100644
--- a/pkg/core/interop_system_core_test.go
+++ b/pkg/core/interop_system_core_test.go
@@ -967,3 +967,18 @@ func TestRuntimeCheckWitness(t *testing.T) {
 		})
 	})
 }
+
+// TestNativeGetMethod is needed to ensure that methods list has the same sorting
+// rule as we expect inside the `ContractMD.GetMethod`.
+func TestNativeGetMethod(t *testing.T) {
+	cfg := config.ProtocolConfiguration{P2PSigExtensions: true}
+	cs := native.NewContracts(cfg)
+	for _, c := range cs.Contracts {
+		t.Run(c.Metadata().Name, func(t *testing.T) {
+			for _, m := range c.Metadata().Methods {
+				_, ok := c.Metadata().GetMethod(m.MD.Name, len(m.MD.Parameters))
+				require.True(t, ok)
+			}
+		})
+	}
+}
diff --git a/pkg/core/native/management.go b/pkg/core/native/management.go
index b30266624..eee25bef6 100644
--- a/pkg/core/native/management.go
+++ b/pkg/core/native/management.go
@@ -614,7 +614,7 @@ func checkScriptAndMethods(script []byte, methods []manifest.Method) error {
 	offsets := bitfield.New(l)
 	for i := range methods {
 		if methods[i].Offset >= l {
-			return errors.New("out of bounds method offset")
+			continue
 		}
 		offsets.Set(methods[i].Offset)
 	}
diff --git a/pkg/core/native/native_neo.go b/pkg/core/native/native_neo.go
index cde774216..7020accc1 100644
--- a/pkg/core/native/native_neo.go
+++ b/pkg/core/native/native_neo.go
@@ -205,7 +205,7 @@ func newNEO(cfg config.ProtocolConfiguration) *NEO {
 	n.AddMethod(md, desc)
 
 	desc = newDescriptor("getCandidateVote", smartcontract.IntegerType,
-		manifest.NewParameter("pubkey", smartcontract.PublicKeyType))
+		manifest.NewParameter("pubKey", smartcontract.PublicKeyType))
 	md = newMethodAndPrice(n.getCandidateVoteCall, 1<<15, callflag.ReadStates)
 	n.AddMethod(md, desc)
 
diff --git a/pkg/core/native/native_test/management_test.go b/pkg/core/native/native_test/management_test.go
index e2c690c16..4f2eb3507 100644
--- a/pkg/core/native/native_test/management_test.go
+++ b/pkg/core/native/native_test/management_test.go
@@ -135,13 +135,20 @@ func TestManagement_ContractDeploy(t *testing.T) {
 		badManifest := cs1.Manifest
 		badManifest.ABI.Methods = make([]manifest.Method, len(cs1.Manifest.ABI.Methods))
 		copy(badManifest.ABI.Methods, cs1.Manifest.ABI.Methods)
-		badManifest.ABI.Methods[0].Offset = 100500 // out of bounds
+		badManifest.ABI.Methods[0].Offset = 100500 // out of bounds, but it's OK, this method will not be checked then.
 		manifB, err := json.Marshal(&badManifest)
 		require.NoError(t, err)
 
-		managementInvoker.InvokeFail(t, "out of bounds method offset", "deploy", nefBytes, manifB)
-	})
+		tx := c.PrepareInvokeNoSign(t, "deploy", nefBytes, manifB)
+		tx.Signers = []transaction.Signer{{}} // Need dummy signer to deploy.
+		b := c.NewUnsignedBlock(t, tx)
+		ic := c.Chain.GetTestVM(trigger.Application, tx, b)
+		t.Cleanup(ic.Finalize)
 
+		ic.VM.LoadWithFlags(tx.Script, callflag.All)
+		err = ic.VM.Run()
+		require.NoError(t, err)
+	})
 	t.Run("bad methods in manifest 2", func(t *testing.T) {
 		var badManifest = cs1.Manifest
 		badManifest.ABI.Methods = make([]manifest.Method, len(cs1.Manifest.ABI.Methods))
@@ -153,6 +160,26 @@ func TestManagement_ContractDeploy(t *testing.T) {
 
 		managementInvoker.InvokeFail(t, "some methods point to wrong offsets (not to instruction boundary)", "deploy", nefBytes, manifB)
 	})
+	t.Run("duplicated methods in manifest 1", func(t *testing.T) {
+		badManifest := cs1.Manifest
+		badManifest.ABI.Methods = make([]manifest.Method, len(cs1.Manifest.ABI.Methods))
+		copy(badManifest.ABI.Methods, cs1.Manifest.ABI.Methods)
+		badManifest.ABI.Methods[0] = badManifest.ABI.Methods[1] // duplicates
+		manifB, err := json.Marshal(&badManifest)
+		require.NoError(t, err)
+
+		managementInvoker.InvokeFail(t, "duplicate method specifications", "deploy", nefBytes, manifB)
+	})
+	t.Run("duplicated events in manifest 1", func(t *testing.T) {
+		badManifest := cs1.Manifest
+		badManifest.ABI.Methods = make([]manifest.Method, len(cs1.Manifest.ABI.Methods))
+		copy(badManifest.ABI.Methods, cs1.Manifest.ABI.Methods)
+		badManifest.ABI.Events = []manifest.Event{{Name: "event"}, {Name: "event"}} // duplicates
+		manifB, err := json.Marshal(&badManifest)
+		require.NoError(t, err)
+
+		managementInvoker.InvokeFail(t, "duplicate event names", "deploy", nefBytes, manifB)
+	})
 
 	t.Run("not enough GAS", func(t *testing.T) {
 		tx := managementInvoker.NewUnsignedTx(t, managementInvoker.Hash, "deploy", nefBytes, manifestBytes)
diff --git a/pkg/rpc/server/server_test.go b/pkg/rpc/server/server_test.go
index 8917c1e41..1c15f9ddf 100644
--- a/pkg/rpc/server/server_test.go
+++ b/pkg/rpc/server/server_test.go
@@ -75,7 +75,7 @@ const (
 	nfsoContractHash           = "c7ec8e0fb4d669913e4ffdd4ba4fa3502e5d2d10"
 	nfsoToken1ID               = "7e244ffd6aa85fb1579d2ed22e9b761ab62e3486"
 	invokescriptContractAVM    = "VwIADBQBDAMOBQYMDQIODw0DDgcJAAAAAErZMCQE2zBwaEH4J+yMqiYEEUAMFA0PAwIJAAIBAwcDBAUCAQAOBgwJStkwJATbMHFpQfgn7IyqJgQSQBNA"
-	block20StateRootLE         = "93ebfc8b030de02c5548ae08ac4a0ea39c12c82e62609ae07bdf3d803bcf9ffd"
+	block20StateRootLE         = "3cba730383c4c2c34475939a4efe9de9ac377bffaf0abdb6f8a1a8fe145d8f69"
 )
 
 var (