CA SCM Harvest Workbench E0306003e: Could not connect to Broker

In CA SCM Harvest Workbench, Version 12. 1..1.141 We face below error while check our or promoted. not always but frequently. what should be done to overcome this issue ? I tried to reinstall PEC in user maching, but it didnt fix. Any solutions ??

E0306003e: Could not connect to Broker: /pt_HBroker://r62dp10/0/haprd5 (Error Code = -307)