Hi Ritesh,
You haven't mentioned error in detail. Please always try to mention detailed error message for quick resolution. Don't worry it happens in early days.
I hope this is due to Control indicator for Controlling are not maintained.
In the transaction code OKKP, Select relevant Controlling Area. Click on Activate Components/Control Indicators
Check Existing Fiscal Year Intervals are maintain. If not then maintain it by clicking New Entries.
Double click on Interval and activate relevant Components and Control Indicators.
Click on Assignment of Company code and check your company code is assigned here. If not then please assign it by clicking New Entries.
Try this and reply. If resolved then please assign points and close this thread.
Regards,
Prakash.