diff --git a/.gitignore b/.gitignore
index 7437dfe..89bd77f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -26,3 +26,8 @@
 # End of https://www.gitignore.io/api/go
 
 .idea/
+
+# Config VSCode IDE
+.vscode
+
+build/
\ No newline at end of file
diff --git a/client.go b/client.go
index 34c5012..003a625 100644
--- a/client.go
+++ b/client.go
@@ -13,6 +13,8 @@ import (
 	"net/url"
 	"path"
 	"strings"
+
+	"github.com/bizflycloud/gobizfly/utils"
 )
 
 const (
@@ -117,7 +119,11 @@ func WithHTTPClient(client *http.Client) Option {
 // WithRegionName sets the client region for Bizfly client.
 func WithRegionName(region string) Option {
 	return func(c *Client) error {
-		c.regionName = region
+		regionName, err := utils.ParseRegionName(region)
+		if err != nil {
+			return err
+		}
+		c.regionName = regionName
 		return nil
 	}
 }
diff --git a/client_test.go b/client_test.go
index 6479d8c..ba2f0c8 100644
--- a/client_test.go
+++ b/client_test.go
@@ -22,7 +22,7 @@ func setup() {
 	serverTest = httptest.NewServer(mux)
 
 	var err error
-	testRegion := "HN"
+	testRegion := "HaNoi"
 	client, err = NewClient(WithAPIUrl(serverTest.URL), WithRegionName(testRegion))
 	services := []*Service{
 		{Name: "Cloud Server",
diff --git a/constants/constants.go b/constants/constants.go
new file mode 100644
index 0000000..9d5c705
--- /dev/null
+++ b/constants/constants.go
@@ -0,0 +1,15 @@
+package constants
+
+const (
+	HaNoiRegion     = "HaNoi"
+	HoCHiMinhRegion = "HoChiMinh"
+	VcHaNoiRegion   = "VC-HaNoi"
+)
+
+var RegionMapping = map[string]string{
+	"hn":        HaNoiRegion,
+	"hanoi":     HaNoiRegion,
+	"hcm":       HoCHiMinhRegion,
+	"hochiminh": HoCHiMinhRegion,
+	"vc-hanoi":  VcHaNoiRegion,
+}
diff --git a/errors/errors.go b/errors/errors.go
new file mode 100644
index 0000000..977e1b9
--- /dev/null
+++ b/errors/errors.go
@@ -0,0 +1,49 @@
+package gobizflyErr
+
+import (
+	"bytes"
+	"html/template"
+)
+
+var tmpl = template.New("GobizflyTemplate")
+
+type GobizflyErr struct {
+	Message  string
+	Code     string
+	Metadata map[string]interface{}
+}
+
+func (err GobizflyErr) Error() string {
+	message := err.GetMessage()
+	return message
+}
+
+func (err GobizflyErr) String() string {
+	message := err.GetMessage()
+	return message
+}
+
+func (err GobizflyErr) GetMessage() string {
+	newTmpl, tmplErr := tmpl.Parse(err.Message)
+	if tmplErr != nil {
+		return err.Message
+	}
+	var result bytes.Buffer
+	tmplErr = newTmpl.Execute(&result, err.Metadata)
+	if tmplErr != nil {
+		return err.Message
+	}
+	return result.String()
+}
+
+func (err GobizflyErr) SetMetadata(metadata map[string]interface{}) GobizflyErr {
+	err.Metadata = metadata
+	return err
+}
+
+var (
+	InvalidRegion = GobizflyErr{
+		Message: "Invalid region {{.Region}}",
+		Code:    "InvalidRegion",
+	}
+)
diff --git a/utils/parser.go b/utils/parser.go
new file mode 100644
index 0000000..fffd9bf
--- /dev/null
+++ b/utils/parser.go
@@ -0,0 +1,17 @@
+package utils
+
+import (
+	"strings"
+
+	"github.com/bizflycloud/gobizfly/constants"
+	gobizflyErr "github.com/bizflycloud/gobizfly/errors"
+)
+
+func ParseRegionName(region string) (string, error) {
+	lowerRegion := strings.ToLower(region)
+	regionName, ok := constants.RegionMapping[lowerRegion]
+	if !ok {
+		return "", gobizflyErr.InvalidRegion.SetMetadata(map[string]interface{}{"Region": region})
+	}
+	return regionName, nil
+}