diff --git a/india_compliance/gst_india/api_classes/base.py b/india_compliance/gst_india/api_classes/base.py
index a986497083..b61a2539b8 100644
--- a/india_compliance/gst_india/api_classes/base.py
+++ b/india_compliance/gst_india/api_classes/base.py
@@ -154,6 +154,10 @@ def _make_request(
                     )
 
             response_json = self.process_response(response_json)
+
+            if response_json.get("error_type") == "invalid_public_key":
+                return self._make_request(method, endpoint, params, headers, json)
+
             return response_json.get("result", response_json)
 
         except Exception as e:
diff --git a/india_compliance/gst_india/api_classes/returns.py b/india_compliance/gst_india/api_classes/returns.py
index 0b74c67b52..45ffd74ecd 100644
--- a/india_compliance/gst_india/api_classes/returns.py
+++ b/india_compliance/gst_india/api_classes/returns.py
@@ -22,8 +22,12 @@
 class PublicCertificate(BaseAPI):
     BASE_PATH = "static"
 
-    def get_gstn_public_certificate(self) -> str:
+    def get_gstn_public_certificate(self, error_message=None) -> str:
         response = self.get(endpoint="gstn_g2b_prod_public")
+
+        if response.certificate == self.settings.gstn_public_certificate:
+            frappe.throw(error_message or _("Public Certificate is already up to date"))
+
         self.settings.db_set("gstn_public_certificate", response.certificate)
 
         return response.certificate
@@ -232,6 +236,7 @@ class ReturnsAPI(ReturnsAuthenticate):
         "AUTH4038": "authorization_failed",  # Session Expired
         "RET11402": "authorization_failed",  # API Authorization Failed for 2A
         "RET2B1010": "authorization_failed",  # API Authorization Failed for 2B
+        "TEC4002": "invalid_public_key",
     }
 
     def setup(self, company_gstin):
@@ -336,6 +341,14 @@ def handle_error_response(self, response):
                 title=_("API Request Failed"),
             )
 
+        # Handle invalid public key
+        if response.error_type == "invalid_public_key":
+            PublicCertificate().get_gstn_public_certificate(
+                error_message=_(
+                    "Looks like Public Key of GSTN used for encryption is Invalid"
+                )
+            )
+
     def is_ignored_error(self, response):
         error_code = response.get("error", {}).get("error_cd")