How to avoid the license key error in kibana with flexmonster pivot table?

HI ,
 
I am now able to see the interface of flexmonster Pivot table in Kibana.. but i have a licence key error. I have change the licence key as you say in the configuration file by a trial one but kibana says that my trial period has expired, that is not the case because i have 30 days trial period. 
See the attached image file.
Help please,
 
Cordialy
Ahadi