Rectification of mistake u/s 154

go for appeal, but beforehand, get in touch with any local CA, and get your documents scurtinized by CA, he will advise the merits level of your case. 

he  Assesse has efiled the ITR 1 return showing the interest on housing loan paid ( Self occupied) by not putting the negative (-) sign a clerical mistake. The assessing officer assessed the same as positive income and raised the demand  by completing the assessment u/s 143 (1) a. On receiving the intimation I have applied for revision u/s 154 stating the facts of the case. But the assessing Officer rejected the petition on the grounds that the rectification leads to reduction of income.Please advise how to rectify the mistake.

YOU SHOULD FILE  REVISED RETURN U/S 139(5) AND CORRECT THE MISTAKE BY THRIUGH E FILLING .