Crystal Report turns out blank after adding a data table and the corresponding field into report designer

I have got a requirement to add customer part number into purchase order report. Since that field does not exist i have added the field using left outer join with oe_line table through custom datastream maintenance and then added that code in .xsd file. I was able to populate that field in LINEXXXDEF data table and so far so good as when i run the report it shows data. As i need it in a seperate detail section, i created another data table and linked the parent key of new data table (CUSPNOXXDEF) to key of LINEXXXDEF as it was done for other similar datatables. But when i save everything and try to run the report, the report shows as blank. I checked the backend xml datastream using developer tools and i see value populated for this field in LINEXXXDEF, but i dont see any code related to the new data table (CUSPNOXXDEF). I refreshed the data many times, redid the table links, tried to change different links, but nothing is working. Any inputs. Do let me know if you need any additional information regarding this issue.

Did you add the data to the XML file in Crystal? If you didn’t it will never show there.
Also, did you run your sql in SSMS and verify that it returns results?