Which Design Code you are using for the member design ?
If it is IS:800-2007 code - Limit State Method of Design, then instead of using UNT, UNB and UNL, please use the LX Parameter. For the details of the parameter list please refer to the section 11F.4 of the Online Help Manual on the topic of "Design Parameters - Indian Codes - Steel Design per IS 800:2007".
However, LY and LZ parameters should work. In case it does not, please upload the STAAD input file here to have a look into the details and mention the member number. Also please mention the Version and Build of the STAAD.Pro that you are using.
If it is IS:800-2007 code - Limit State Method of Design, then instead of using UNT, UNB and UNL, please use the LX Parameter. For the details of the parameter list please refer to the section 11F.4 of the Online Help Manual on the topic of "Design Parameters - Indian Codes - Steel Design per IS 800:2007".
However, LY and LZ parameters should work. In case it does not, please upload the STAAD input file here to have a look into the details and mention the member number. Also please mention the Version and Build of the STAAD.Pro that you are using.