diff --git a/signup-service/src/test/java/io/mosip/signup/controllers/RegistrationControllerTest.java b/signup-service/src/test/java/io/mosip/signup/controllers/RegistrationControllerTest.java
index ed7641c9..761b7f17 100644
--- a/signup-service/src/test/java/io/mosip/signup/controllers/RegistrationControllerTest.java
+++ b/signup-service/src/test/java/io/mosip/signup/controllers/RegistrationControllerTest.java
@@ -519,6 +519,23 @@ public void doGenerateChallenge_withRegistrationPurpose_thenPass() throws Except
                 .andExpect(jsonPath("$.errors").isEmpty());
     }
 
+    @Test
+    public void doGenerateChallenge_withNullPurpose_returnErrorResponse() throws Exception {
+        String status = "SUCCESSFUL";
+        GenerateChallengeResponse generateChallengeResponse = new GenerateChallengeResponse(status);
+        generateChallengeRequest.setPurpose(null);
+        when(registrationService.generateChallenge(generateChallengeRequest, ""))
+                .thenReturn(generateChallengeResponse);
+
+        mockMvc.perform(post("/registration/generate-challenge")
+                        .content(objectMapper.writeValueAsString(wrapper))
+                        .contentType(MediaType.APPLICATION_JSON))
+                .andExpect(status().isOk())
+                .andExpect(jsonPath("$.response").isEmpty())
+                .andExpect(jsonPath("$.errors").isNotEmpty())
+                .andExpect(jsonPath("$.errors[0].errorCode").value(ErrorConstants.INVALID_PURPOSE));
+    }
+
     @Test
     public void doGenerateChallenge_withResetPasswordPurpose_thenPass() throws Exception {
         String status = "SUCCESSFUL";