Problems with input voltage compensation LNK603

Hello,

I desinged a flyback circuit with LNK603 and have some problems with des variation of the input voltage. The device should work from 195V up to 264V AC. Output is 3V 200mA. The design is without Bias winding. The output characteristic is strongly dependend on the input voltage (picture). The difference is more than +-10%. Is there a possibility to influence that with an external circuit? Do you know where the reason could be.

Thanks a lot

Dense