Forms :: ORA-00933 When Calling Report From A Form

I have added a text field on forms 6i which calls reportAfter adding the new field called "appeal_name" it gave me the desired result for two three times and somehow after that it started to throw this error

ORA- 00933. I did try to find solution on the web and was given the hint that this occurs due to space or indentation in the coding. I have used Ltrim and Rtrim to remove any space when I added the text field "appeal_name", Following code has been added

if
upper(ltrim(rtrim(:appeal_name)))!='ALL' then
where_cond:=ltrim(rtrim(where_cond))||' and upper (tbl_donation.appeal_code)='''||:blk_hsbt.appeal_code||'''';
elsif :appeal_name is null then
where_cond:=ltrim(rtrim(where_cond))||' and tbl_donation.appeal_code is null';
end if;