vCACCAFEHost.getHostWithCredentials problem

I am trying to create temporary vCAC host using the api host = vCACCAFEHost.getHostWithCredentials(Username,Password); I also tried the vCACCAFEHost.getHostForTenant and I always get following exception with cannot find function. Do I need to do something?

2016-03-05 21:51:08.756] [E] Error in (Workflow:SapScaleUp / Construct BP Object (item6)#1) TypeError: Cannot find function getHostWithCredentials in object DynamicWrapper (Class) : [vCACCAFEHost]-[class com.vmware.o11n.plugin.vcac.model.VCACHost] -- VALUE : null.

[2016-03-05 21:51:08.777] [E] [class com.vmware.o11n.plugin.vcac.model.VCACHost] -- VALUE : null. (Workflow:SapScaleUp / Construct BP Object (item6)#1)'