diff --git a/lib/conversation.ts b/lib/conversation.ts
index 060e96e9..0b7d249c 100644
--- a/lib/conversation.ts
+++ b/lib/conversation.ts
@@ -142,8 +142,7 @@ export default class Conversation {
         withRunningAssignmentRules = false,
     }: AssignConversationData) {
         const url = `/${this.baseUrl}/${id}${
-            withRunningAssignmentRules ? '/run_assignment_rules' : ''
-        }/parts`;
+            withRunningAssignmentRules ? '/run_assignment_rules' : '/parts'}`;
         const data: AssignConversationRequest | undefined =
             withRunningAssignmentRules
                 ? undefined
diff --git a/test/unit/conversation.test.ts b/test/unit/conversation.test.ts
index 3a3c628d..5feab871 100644
--- a/test/unit/conversation.test.ts
+++ b/test/unit/conversation.test.ts
@@ -321,7 +321,7 @@ describe('conversations', () => {
         const expectedReply = {};
 
         nock('https://api.intercom.io')
-            .post(`/conversations/${id}/run_assignment_rules/parts`)
+            .post(`/conversations/${id}/run_assignment_rules`)
             .reply(200, expectedReply);
 
         const client = new Client({