diff --git a/package.json b/package.json
index 8ddec11..27bb6b6 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "lhisp-oauth-client-dev",
-  "version": "1.0.32",
+  "version": "1.0.33",
   "main": "src/index",
   "types": "src/index.d.ts",
   "repository": {
diff --git a/src/lhisp-oauth-client.ts b/src/lhisp-oauth-client.ts
index 54816b7..a9f3e64 100644
--- a/src/lhisp-oauth-client.ts
+++ b/src/lhisp-oauth-client.ts
@@ -151,6 +151,10 @@ export class LhispOauthClient<iAccessToken extends AccessToken = AccessToken> {
       return this.formatAccessToken(this.accessToken);
     }
 
+    if (!this.accessToken) {
+      throw new Error("Access Token não disponível.");
+    }
+
     return `${this.accessToken?.token_type} ${this.accessToken?.access_token}`;
   }