diff --git a/pkg/asset/ast.go b/pkg/asset/ast.go
index 69f6caf4d..86fb873ed 100644
--- a/pkg/asset/ast.go
+++ b/pkg/asset/ast.go
@@ -8,7 +8,7 @@ import (
 	"github.com/goccy/go-yaml/ast"
 )
 
-func UpdateASTFile(file *ast.File, pkgs interface{}) error {
+func UpdateASTFile(file *ast.File, pkgs interface{}) error { //nolint:cyclop
 	node, err := yaml.ValueToNode(pkgs)
 	if err != nil {
 		return fmt.Errorf("convert packages to node: %w", err)
@@ -20,7 +20,11 @@ func UpdateASTFile(file *ast.File, pkgs interface{}) error {
 			continue
 		}
 		for _, mapValue := range body.Values {
-			if mapValue.Key.String() != "packages" {
+			key, ok := mapValue.Key.(*ast.StringNode)
+			if !ok {
+				continue
+			}
+			if key.Value != "packages" {
 				continue
 			}
 			switch mapValue.Value.Type() {
diff --git a/pkg/controller/generate/output/insert.go b/pkg/controller/generate/output/insert.go
index 69aa33965..3db3eefe5 100644
--- a/pkg/controller/generate/output/insert.go
+++ b/pkg/controller/generate/output/insert.go
@@ -45,7 +45,11 @@ func (o *Outputter) generateInsert(cfgFilePath string, pkgs []*aqua.Package) err
 
 func getPkgsAST(values []*ast.MappingValueNode) *ast.MappingValueNode {
 	for _, mapValue := range values {
-		if mapValue.Key.String() != "packages" {
+		key, ok := mapValue.Key.(*ast.StringNode)
+		if !ok {
+			continue
+		}
+		if key.Value != "packages" {
 			continue
 		}
 		return mapValue
diff --git a/pkg/controller/update/ast/package.go b/pkg/controller/update/ast/package.go
index 86cf64aea..fbf2018e8 100644
--- a/pkg/controller/update/ast/package.go
+++ b/pkg/controller/update/ast/package.go
@@ -43,7 +43,11 @@ func parsePackageNode(logE *logrus.Entry, node ast.Node, newVersions map[string]
 	var pkgVersion string
 	var nameNode *ast.StringNode
 	for _, mvn := range mvs {
-		switch mvn.Key.String() {
+		key, ok := mvn.Key.(*ast.StringNode)
+		if !ok {
+			continue
+		}
+		switch key.Value {
 		case "registry":
 			sn, ok := mvn.Value.(*ast.StringNode)
 			if !ok {
diff --git a/pkg/controller/update/ast/registry.go b/pkg/controller/update/ast/registry.go
index 3eacc64fc..847007c0e 100644
--- a/pkg/controller/update/ast/registry.go
+++ b/pkg/controller/update/ast/registry.go
@@ -11,7 +11,11 @@ const typeStandard = "standard"
 
 func findMappingValue(values []*ast.MappingValueNode, key string) *ast.MappingValueNode {
 	for _, value := range values {
-		if value.Key.String() == key {
+		sn, ok := value.Key.(*ast.StringNode)
+		if !ok {
+			continue
+		}
+		if sn.Value == key {
 			return value
 		}
 	}
@@ -65,7 +69,11 @@ func parseRegistryNode(logE *logrus.Entry, node ast.Node, newVersions map[string
 	var newVersion string
 	var rgstName string
 	for _, mvn := range mvs {
-		switch mvn.Key.String() {
+		key, ok := mvn.Key.(*ast.StringNode)
+		if !ok {
+			continue
+		}
+		switch key.Value {
 		case "ref":
 			sn, ok := mvn.Value.(*ast.StringNode)
 			if !ok {