Zoho Flow - Hubspot CRM connection

Zoho Flow - Hubspot CRM connection

Hi  - has anyone set up a connection between Zoho Flow and Hubspot CRM?  I have set up a Flow which polls for updates to Deals in Hubspot and - depending on certain conditions -  creates an account and contact in Zoho CRM from information in Hubspot. This works fine when I use the 'Test and Debug' utility in Flow. However when the Flow is switched on and left to "Poll" for updates  the flow does not seem to  trigger when an update is made  to a Deal in  Hubspot.  I wondered if this is an issue anyone else has come up against. - and if anyone has a solution?