question about CRI in reporting service

Question

 have question please and need your help

i have developed Custom Reporting item , i have make simple user control and sure it is done in win form , and then i took this control and have made design time component and run time component and i deploy me item,and it appear in report item toolbox , but when i tried to drag this control in the report there is an error appear : the method or operation is not implemented

please can any one tell me what is the cause of this error

best regards,