Problem changing from synchronous to Asynchronous

[Ilyass]

Hello, 

I am having an issu using my print Geoprocessing Service in ArcGIS Server Manager.

I wanted to change the execution mode from synchronous to Asynchronous but i am having this error:

Error performing execute operation Error handling service request :Request type is not supported. 'Execute' asynchronous GP service.

Need Help ?

Thanks a lot

[Ilyass]

Hello,

In order to give more detail for my request.

while changing to Asynchronous mode of execution i am checking LOG of my arcgis server manager and i am getting this : 

SEVERE       23 oct. 2017 14:50:29        Error performing execute operation Error handling service request :Request type is not supported. 'Execute' asynchronous GP service.   
SEVERE    23 oct. 2017 14:50:13            There is an error drawing layer: Plan de fond (forme linéaire)                         
SEVERE    23 oct. 2017 14:50:13            There is an error during the draw Plan de fond (forme linéaire) (1.) The number of points is less than required for feature. 

Please it's urgent, nead help !!!

Thanks in advance