# Async chat completion stuck in IN\_PROGRESS for hours while sync returns successfully

**URL:** <https://community.perplexity.ai/t/async-chat-completion-stuck-in-in-progress-for-hours-while-sync-returns-successfully/3661>\
**Category:** Bug Reports\
**Created:** [January 24, 2026, 2:57am UTC](https://community.perplexity.ai/t/async-chat-completion-stuck-in-in-progress-for-hours-while-sync-returns-successfully/3661 "2026-01-24T02:57:51Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Ashutosh\_Joshi](https://sea1.discourse-cdn.com/flex001/user_avatar/community.perplexity.ai/ashutosh_joshi/32/383_2.png) [@Ashutosh\_Joshi](https://community.perplexity.ai/u/Ashutosh_Joshi)\
**Post date:** [January 24, 2026, 2:57am UTC](https://community.perplexity.ai/t/async-chat-completion-stuck-in-in-progress-for-hours-while-sync-returns-successfully/3661/1 "2026-01-24T02:57:51Z")

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We are observing inconsistent and unexpected behavior between **sync** and **async** chat completion modes for the same query and model.

- In **sync mode** , the request completes successfully and returns the expected response in approximately **20 seconds**.

- In **async mode** , the same request remains in **`IN_PROGRESS`** status for an unusually long duration ( **2–3 hours** ), without failure or intermediate status updates.

- When the async request finally completes, the timestamps indicate that the actual execution time was **approximately 1 minute** , suggesting that the job was queued or stalled for hours before being executed.

* * *

### **Details**

- **Model:** `sonar-deep-research`

- **Query:** Same exact user query used in both sync and async modes

#### **Sync Mode Result**

- Status: `COMPLETED`

- Response time: ~20 seconds

#### **Async Mode Result**

- Status: `IN_PROGRESS` for ~2–3 hours

- No failure or error reported during this period

- Eventually transitions to `COMPLETED`

* * *

### **Key Observation (Important)**

From the async job metadata:

```auto
"created_at": 1768991705,
"started_at": 1768991705,
"completed_at": 1768991768

```

This indicates:

- The async job **completed in ~63 seconds**

- However, the client observed the job in `IN_PROGRESS` state for **multiple hours** before this completion was surfaced

This suggests the async job may have been:

- Queued or delayed for an extended period before actual execution, or

- Executed earlier but completion status was not updated or returned promptly

* * *

### **Async Job State During Delay**

During the extended delay:

- `status`: `IN_PROGRESS`

- `completed_at`: `null`

- `failed_at`: `null`

- `error_message`: `null`

No indication was provided that the job was queued, paused, or delayed.

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<div class="post-metadata">

**Author:** ![Will\_Swannell](https://sea1.discourse-cdn.com/flex001/user_avatar/community.perplexity.ai/will_swannell/32/2580_2.png) [@Will\_Swannell](https://community.perplexity.ai/u/Will_Swannell)\
**Post date:** [February 1, 2026, 9:28pm UTC](https://community.perplexity.ai/t/async-chat-completion-stuck-in-in-progress-for-hours-while-sync-returns-successfully/3661/2 "2026-02-01T21:28:11Z")

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This is happening to me too.

It seems to happen if I poll before it completes..

It’s killing my app in production which is incredibly frustrating to happen from a larger platform like this.. Please can someone look at this! I’m happy to provide specific details.

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<div class="post-metadata">

**Author:** ![Ashutosh\_Joshi](https://sea1.discourse-cdn.com/flex001/user_avatar/community.perplexity.ai/ashutosh_joshi/32/383_2.png) [@Ashutosh\_Joshi](https://community.perplexity.ai/u/Ashutosh_Joshi)\
**Post date:** [February 3, 2026, 6:13am UTC](https://community.perplexity.ai/t/async-chat-completion-stuck-in-in-progress-for-hours-while-sync-returns-successfully/3661/3 "2026-02-03T06:13:49Z")

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The solution I found is to use `cache=false` in the polling API. With this, it returns a successfully completed response when the task finishes. This appears to be a caching issue in the Perplexity API.