farm level feature - timer job and service - reactivation error

 I am programmatically deleting the custom service and associated jobs on custom farm level feature deactivation.

On reactivation, am getting sql error

SqlError: 'The INSERT statement conflicted with the FOREIGN KEY SAME TABLE constraint "FK_Objects_Objects". The conflict occurred in database "SharePoint_Config", table "dbo.Objects", column 'Id'.

But if i recycle the central admin app pool as it is farm level feature, reactivation occurs without this error.

Any help much appreciated :)