I'm trying to set up a flow that adds a comment to an existing viva engage post but I'm struggling to make it work, hoping someone can help me troubleshoot or tell me if this is even possible.

My first flow that works:

user submits form
flow creates new sharepoint list item
flow then creates a viva engage post
flow updates sharepoint list item with:
- post url
- message id - sharepoint list field VEMessageID (CHECK NEXT FLOW - I reference this one)
- thread id

Second flow flow that doesn't work:

item is modified (this part works)
- I have a trigger condition to check if my yes/no field "Share update" = true
get item (this part works)
update item (this part works)
- updates yes/no "Share update" field back to no so this won't run in a cycle
post message DOESN'T WORK - HELP!
- I set the Post message action parameter "Replied to ID" as the message id field on the sharepoint list
  - field name is VEMessage ID
  - field is the id of the message from the original post from the first flow (See above)