How do i know what did i do wrong on my i-765 form?

You should have sent $1070 only. There is no fee required for the I-765 when filed with the I-485. See I-485 instructions: a href="http://www.uscis.gov/portal/site/uscis/menuitem.5af9bb95919f35e66f614176543f6d1a/?vgnextoid=3faf2c1a6855d010VgnVCM10000048f3d6a1RCRD&vgnextchannel=db029c7755cb9010VgnVCM10000045f3d6a1RCRD" rel="nofollow"http://www.uscis.gov/portal/site/uscis/m…/a