diff --git a/fields/extract.go b/fields/extract.go
index 96c172a..777a541 100644
--- a/fields/extract.go
+++ b/fields/extract.go
@@ -54,7 +54,7 @@ func downloadJar(url *url.URL, outputDir string) (string, error) {
 		}
 	}
 	if uncompressedReader == nil {
-		return "", fmt.Errorf("unable to find .deb data file")
+		return "", errors.New("unable to find .deb data file")
 	}
 
 	tarReader := tar.NewReader(uncompressedReader)
@@ -86,7 +86,7 @@ func downloadJar(url *url.URL, outputDir string) (string, error) {
 	}
 
 	if aceJar == nil {
-		return "", fmt.Errorf("unable to find ace.jar")
+		return "", errors.New("unable to find ace.jar")
 	}
 
 	defer aceJar.Close()
@@ -192,7 +192,6 @@ func extractJSON(jarFile, fieldsDir string) error {
 			if err != nil {
 				return fmt.Errorf("unable to read file: %w", err)
 			}
-
 		}
 		fmt.Println(file.Name(), file.IsDir())
 	}
diff --git a/fields/main_test.go b/fields/main_test.go
index 561b754..f45bfd0 100644
--- a/fields/main_test.go
+++ b/fields/main_test.go
@@ -151,7 +151,7 @@ func TestResourceTypes(t *testing.T) {
 
 		err := resource.processJSON(([]byte)(testData))
 
-		assert.Empty(t, err, "No error processing JSON")
+		assert.NoError(t, err, "No error processing JSON")
 		assert.Equal(t, expectation.StructName, resource.StructName)
 		assert.Equal(t, expectation.ResourcePath, resource.ResourcePath)
 		assert.Equal(t, expectation.Types, resource.Types)
diff --git a/unifi/unifi.go b/unifi/unifi.go
index 2ce70f6..516a9a9 100644
--- a/unifi/unifi.go
+++ b/unifi/unifi.go
@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"context"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"io"
 	"net/http"
@@ -183,7 +184,7 @@ func (c *Client) Login(ctx context.Context, user, pass string) error {
 	c.version = si.Version
 
 	if c.version == "" {
-		return fmt.Errorf("unable to determine controller version")
+		return errors.New("unable to determine controller version")
 	}
 
 	return nil
@@ -225,7 +226,7 @@ func (c *Client) do(ctx context.Context, method, relativeURL string, reqBody int
 	req.Header.Add("Content-Type", "application/json; charset=utf-8")
 
 	if c.csrf != "" {
-		req.Header.Set("X-CSRF-Token", c.csrf)
+		req.Header.Set("X-Csrf-Token", c.csrf)
 	}
 
 	resp, err := c.c.Do(req)
@@ -238,8 +239,8 @@ func (c *Client) do(ctx context.Context, method, relativeURL string, reqBody int
 		return &NotFoundError{}
 	}
 
-	if csrf := resp.Header.Get("x-csrf-token"); csrf != "" {
-		c.csrf = resp.Header.Get("x-csrf-token")
+	if csrf := resp.Header.Get("X-Csrf-Token"); csrf != "" {
+		c.csrf = resp.Header.Get("X-Csrf-Token")
 	}
 
 	if resp.StatusCode != http.StatusOK {
diff --git a/unifi/user.go b/unifi/user.go
index 06106c5..b939c8c 100644
--- a/unifi/user.go
+++ b/unifi/user.go
@@ -2,6 +2,7 @@ package unifi
 
 import (
 	"context"
+	"errors"
 	"fmt"
 )
 
@@ -54,7 +55,7 @@ func (c *Client) CreateUser(ctx context.Context, site string, d *User) (*User, e
 	}
 
 	if len(respBody.Data) != 1 {
-		return nil, fmt.Errorf("malformed group response")
+		return nil, errors.New("malformed group response")
 	}
 
 	if err := respBody.Data[0].Meta.error(); err != nil {