maximum Token for iControl API

We are automating F5 configuration via IControl API. In our testing, see the error msg below: 018-03-23 16:12:01.512+1100 vco: [component="SCRIPTING_LOG" priority="ERROR" thread="WorkflowExecutorPool-Thread-16451" user="" context="" token="8a0bd2a9624833390162514551a1516d" wfid="7c21a3c8-720f-4265-9518-6a6300c6755e" wfname="DWF F5 LTM Create ServerSSL Profile" anctoken="" wfstack="7c21a3c8-720f-4265-9518-6a6300c6755e" instanceid=""] Workflow execution stack:

item: 'Create Server SSL Profile/item2', state: 'failed', business state: 'null', exception: 'HTTP 400 Bad Request: user 21232f29-7a57-35a7-8389-4a0e4a801fc3 has reached maximum active login tokens. Request: POST https://10.138.161.18:443/mgmt/shared/authn/login HTTP/1.1' workflow: 'DWF F5 LTM Create ServerSSL Profile' (7c21a3c8-720f-4265-9518-6a6300c6755e)

From the error msg, looks like we can't get new token for our API as it reached maximum active tokens.

Anybody know the value of allowed maximum active tokens? could we increase the default value? Thanks.