My code is clearing the member description. How to prevent this.

I have a BR that is setting a value in a member's text3 field. In doing this I have the following code which appears to NOT save the member description so it is being cleared.

BRApi.Finance.MemberAdmin.SaveMemberInfo(si, PDOToUpdateInfo, True, True, False, TriStateBool.FalseValue)

I changing the False in the line above to True, the code compiled with no errors, but at runtime I received the error " Error updating member 'IT_PGM_1038_27'. Invalid parameter. Descriptions, IT_PGM_1038_27." What am I doing wrong? I can send more of the code if that would be helpful.