Hi Das,
Firstly this problem might occur if the column width is not large enough.
Secondly we can get this error, when we use the Measures which are coming out of Bex query universes. #UNAVAILABLE occurs when we are using smart measures and Web Intelligence cannot calculate the value based on the contexts used. Do not use smart measures while applying filter on a aggregated value from your query and further aggregate it within the report. At the same time, it will throw the error, when we use it in the formula too
Solution: SAP Note Change the type of measures objects from database delegate to sum.
See also SAP Note: 1606502 and 1603634.
Regards,
Ashvin