How to post slack message in thread of previous message on the channel? Flow designer

[aakankshapl]

Hello all,

We have created a flow using slack scope where we are posting a message in slack channel so after waiting of 2 hours another message should get post on previous message thread on the same channel.

Please help me on this!!!
Thank you in advance.

[SP22]

Don’t hardcode the channel ID value in step 6; instead, use the channel ID data pill from step 4 in Flow Designer to ensure your reply is posted in the correct thread.

[aakankshapl]

When i click on the data pill of channel id, this is how it looks:

[SP22]

@aakankshapl,

Step‑by‑step in Flow Designer

1) Post the initial message

• Action: Slack → Post Message
• Inputs: Select your Slack connection; set Channel (by name or ID) and Text.
• Outputs to keep:
  • Channel ID (from the action’s outputs)
  • Message timestamp (Slack ts) — this becomes your thread id (thread_ts) for the next post.

  Slack threads are keyed by the parent message’s ts. You’ll reuse it as thread_ts in the follow‑up step.

2) Wait for two hours

• Flow logic: Wait for a duration → Explicit duration = 2 hours
  • Notes: Flow Designer’s Wait for a duration supports explicit/relative waits (up to 999 hours) and the actual firing time can vary slightly due to engine processing. That’s normal.

3) Post the follow‑up in the same thread

You have two straightforward options depending on your Slack Spoke version:

Use a “Thread timestamp” input (if present in your Post Message action)

• Action: Slack → Post Message
• Channel: Use the Channel ID from Step 1 outputs
• Thread timestamp: Use the Message timestamp (ts) from Step 1 outputs
• Text: Your follow‑up message

[aakankshapl]

@SP22 

Where to use that Thread timestamp in 2nd post message action as they only asking Channel id,  message, block, username and icon.

Also can you please guide me on how to keep output:

• Channel ID (from the action’s outputs)
• Message timestamp (Slack ts) — this becomes your thread id (thread_ts) for the next post.

It will be a lot of help if this work, I am working on this from last week.
I appreciate your help!