HubSpot has announced that they are doing maintenance on the Engagements API on September 15, 2019 between 5:00 and 6:00 pm Eastern time. The maintenance outage may last up to two minutes.  
 

If a TIBCO Scribe® Solution that accesses the HubSpot Engagements API executes during the outage, you may see errors. Best practice is to analyze your results to ensure that no records were missed. Another option is to pause your Solutions during the outage window.  For additional information, see HubSpot’s maintenance announcement: 

Upcoming: Engagements API Maintenance