SIWAREX U with 315-2DP: calibration

I am using SIWAREX U with 315-2DP and there is some problem with weighing system. when i observe it then i found that for ODD weight (like 300, 500, 700 kg) it shows different value than actual weight so i decided to calibrate it but when i am doing it, during calibration when we send known weight value to PLC against actual value at that time for even value (like- 200,400,600 kg ) send option still enable but for odd value (like 300, 500, 700 kg) send option gets disable.

Please anyone suggest me that how i calibrarte this and how get out this problem.

Thanks !

Rajnish